Court File and Parties

Court File No.: 22-11403959 Date: 2025-08-05 Ontario Superior Court of Justice

Between: His Majesty the King – and – Chau Khanh Lam and Hue Ai Lam Accused

Counsel:

• Tasha Bobrovitz and Julian Whitten for the Crown
• Ewan Lyttle and Brett McGarry for Chau Lam
• Paolo Giancaterino, Amicus Curiae for Hue Lam

Heard: June 30 and July 2, 2025 Oral Decision: July 7, 2025

Ruling on Admissibility of Defence Expert Opinion Evidence – Dr. Bélanger

Somji J.

Introduction

[1] Shortly after midnight on October 31, 2022, the accused Chau Lam called 911 to report that she and her sister Hue Lam had killed their mother (hereinafter "Chau" and "Hue"). Upon police arrival, Cst. Tang asked the Lam sisters what happened. Hue stated and gestured to Cst. Tang that her mother had hit her. Cst. Tang then asked what happened here. Hue pointed to herself and then her sister and then put her hands together in a fist above her head and made a striking motion downward towards her legs. Cst. Tang queried "Both of you hit her?" at which time Hue repeated the motion. The Lam sisters were provided their Charter rights and cautions and exercised their rights to counsel. They were interviewed independently by Detectives Séguin and Brennan that same morning in the presence of a Vietnamese interpreter and both sisters admitted to killing their mother. Both sisters told the officers they were verbally and physically abused by their mother.

[2] The trial commenced on June 9, 2025. The court has heard evidence from the Lam sisters' brothers, Chanh and Min Huynh, that the sisters were emotionally and physically abused by their mother since childhood. Hue's statements and gestures to Cst. Tang and both the statements made by both accused to the detectives were tendered as part of the Crown's case.

[3] The Crown has closed its case, and we are presently in Chau's case. Chau testified in her own defence and stated in examination in chief that she and her sister killed their mother. Chau testified that she and her sister have always lived with their mother and that she cared for her mother all her life. She testified that her mother verbally and physically abused her and her sister since childhood and that this abuse continued even as adults and following their arrival in Canada in 1992. Chau testified that the verbal and physical abuse against her and her sister escalated in the months before the killing and that her sister, diagnosed with Parkinson's disease, was less able to defend herself.

[4] Chau testified about the obligation to care for her mother, why she endured the abuse, why she could not abandon her mother, and why she did not consider calling the police. She also testified about how she perceived the various options available to her to deal with her personal circumstances, including her continued obligation to care for her mother and sister.

[5] Following the close of the Crown's case, defence provided the Crown with a cultural expert report prepared by Dr. Danièle Bélanger. Defence counsel for Chau and amicus curiae for Hue seek to call Dr. Bélanger to provide expert opinion evidence on Vietnamese society, gender, family, and migration. Defence does not seek to have Dr. Bélanger provide any opinion evidence on how these cultural and social mores of Vietnamese society specifically applied to the Lam sisters or to answer any hypothetical questions along these lines. For this reason, I am satisfied that this voir dire and ruling on the admissibility of cultural context evidence can apply to both Lam sisters notwithstanding that at present, we are in Chau's case before the jury.

[6] The following reasons explain why Dr. Bélanger will be permitted to testify as an expert on Vietnamese society, gender, family, and migration subject to the parameters set out below and that her evidence may be considered for both Lam sisters.

The Law on Expert Opinion Evidence

[7] Expert or opinion evidence is presumptively inadmissible. The party leading the evidence must establish on a balance of probabilities that the evidence meets the criteria set out in R. v. Mohan, [1994] 2 S.C.R. 9. The "Mohan factors" have been refined in subsequent cases: see R. v. Abbey, 2009 ONCA 624, 97 O.R. (3d) 330 ("Abbey 1"); R. v. Abbey, 2017 ONCA 640, 140 O.R. (3d) 40 ("Abbey 2"); and White Burgess Langille Inman v. Abbott and Haliburton Co., 2015 SCC 23, [2015] 2 S.C.R. 182.

[8] The admissibility of an expert's opinion, the scope of the evidence to be provided, and the manner of its introduction are to be determined following a voir dire: Abbey 1, at para. 63. This involves a two-step analysis. At the first stage, the party proposing to call the expert must establish the threshold requirements set out in Mohan and later refined in Abbey 2, at para. 48. These are:

a. that the opinion evidence is logically relevant;

b. that the opinion evidence is necessary to assist the trier of fact;

c. that the opinion evidence is not subject to an exclusionary rule;

d. the expert is properly qualified to give the evidence, which includes the requirement that the expert be willing to fulfill their duty to the court to give evidence that is impartial, independent, and unbiased; and

e. if the opinion evidence is based on novel or contested science, the tendering party must establish the reliability of the science for that purpose.

[9] Once these requirements are met, the trial judge must, as a gatekeeper, exercise its judicial discretion to consider whether the benefits of admitting the evidence outweigh its potential risks. This secondary stage, sometimes referred to as the cost-benefit analysis, involves a continued consideration of the threshold factors of relevance, necessity, reliability, and absence of bias and weighing those factors against the consumption of time, and the potential for prejudice, including the likelihood that the evidence will confuse the trier of fact: White Burgess, at paras. 24, 54; Abbey 1, at paras. 76-79; and R. v. McRae, 2018 ONSC 3694, at para. 18.

[10] I must also add that the cost-benefit analysis under the second component of the framework for admission is a specific application of the court's general residual discretion to exclude evidence whose prejudicial effect is greater than its probative value. This general residual discretion is always available to the court, not just when determining whether to admit an item of evidence, but after the admission stage if the evidence's prejudicial effect is only revealed in the course of its presentation to the trier of fact: Bruff-Murphy et al. v. Gunawardena, 2017 ONCA 502, 138 O.R. (3d) 584, at para. 65.

[11] Before deciding admissibility, the trial judge must also delineate the scope of the proposed expert evidence and ensure strict adherence to those boundaries.

Admissibility of Cultural Context Evidence

[12] Cultural evidence is opinion evidence and therefore, subject to the same rules of admissibility that governs all opinion evidence as summarized in Abbey 2, at para. 48 and A.A. v. Z.S.M., 2025 ONCA 283.

[13] Expert evidence about cultural context and mores within communities is a "well-recognized field of study within the academic and professional disciplines": R. v. Shafia, 2016 ONCA 812, 341 C.C.C. (3d) 354, at para. 240; Abbey 1, at para. 121. Such evidence does not need to meet the rigors of testing under the scientific method to be admissible. In fact, much of the expert evidence admitted in courts is in disciplines that are not scientifically validated: Shafia, at para. 240; Abbey 1, at para. 109.

[14] Expert opinion evidence about cultural mores may be relevant to and thus admissible on a variety of issues including to provide context for and to facilitate appreciation of other evidence. Cultural evidence may also be admissible to support a defence and/or to establish intent: Shafia, at para. 241.

[15] In R. v. Shafia, the Crown sought to introduce expert evidence of honour killings as a possible motive for why members of the Shafia family killed three daughters and a first wife. The trial judge admitted expert evidence about "the relationship between culture, religion, patriarchy and violence against women in the Middle East and around the world, specifically as these issues relate to the phenomenon known as honour killings": at para. 201.

[16] On appeal, the expert evidence in Shafia was challenged on the basis that it was anecdotal, could have resulted in dangerous cultural stereotyping and propensity reasoning, and that its probative value was overstated. The Court of Appeal for Ontario found that the expert evidence about cultural mores had been properly admitted. The evidence was relevant to the motive for the murders and assisted the jury in understanding and evaluating material evidence at trial. It was necessary to assist the jury as the specialized knowledge of the expert extended well beyond the everyday experience of the average juror: at paras. 250-51.

[17] Cultural expert evidence on honour killings was similarly admitted in R. v. Sadiqi, 2013 ONCA 250, 305 O.A.C. 150. In that case, the Crown sought to admit expert opinion evidence on the relationship between culture, religion, patriarchy, and violence against women in the Middle East and diasporas around the world, specifically as those issues relate to honour killings. Defence conceded that evidence of the "Afghan culture" and the "cultural perspective of the parties" were relevant to the issues of provocation, planning, and deliberation. However, defence opposed its admissibility on the grounds that the expert was a strong advocate for women's rights. They raised concerns that this could undermine the expert's objectivity and this, combined with the inherently prejudicial use of the phrase "honour killings," could turn the focus of the trial away from whether the Crown had proven the appellant's culpability to issues of domestic abuse: at paras. 10-12.

[18] On appeal, the court rejected the notion that the expert's objectives in educating people about honour killings in an effort to improve women's rights precluded her from being an acceptable expert witness. In assessing whether the potential prejudicial effect was outweighed by its probative value, the court observed that the expert did not know any of the parties involved and would not be offering an opinion on whether the homicides were honour killings or on any other hypothetical fact situation. Rather, her proposed evidence would provide context that could assist the jury in deciding what inferences to draw as to the appellant's state of mind from the facts that the jury found the Crown had established: at paras. 13-16.

[19] Courts have also admitted cultural expert evidence related to other subjects. In R. v. O.S., 2022 ONSC 4217, Akhtar J. admitted expert evidence adduced by the Crown on how misogynistic attitudes within incel groups could have influenced the accused's motivation to murder the deceased. Justice Akhtar ruled the proposed expert evidence was not "novel science" but based on the expert's nine-years of experience and research on incels and their ecosystem. Although not peer reviewed research, the court was satisfied as to the reliability of the opinion evidence based on the expert's academic research and immersion into the subject matter of incel ideology. Justice Akhtar noted that an expert's evidence need not be "perfect" or "foolproof" to be admissible and that any concerns of prejudice could be addressed with a jury instruction: at paras. 39-40, 45.

[20] In R. v. Boswell, 2011 ONCA 283, 280 O.A.C. 283, the court admitted cultural evidence of a "code of silence" that operated within a community living in a high crime, high density area of Toronto in order to facilitate the jury's appreciation of certain evidence presented in a murder case. The Court of Appeal for Ontario found that the evidence of the expert, a police officer in that case, helped the jury understand why a key witness initially lied to the police, delayed identifying the perpetrator, and feared he would be killed for cooperating with the police: at paras. 6-8, 26.

[21] In R. v. Abdulle, 2023 ONCA 32, 166 O.R. (3d) 307, the trial judge found two police officers were qualified as experts to provide opinion evidence on issues related to the general culture and practices of urban street gangs and more specially to the existence and membership into Tandridge Cripz and the rival A-block gang. One expert testified about the general structure, operations, and culture of gangs as well as the membership, practices, and ethos of Tandridge Cripz. The expert was permitted to testify about concepts like gang-controlled territory, the use of violence to protect territory, and violent retaliation in response to insult or acts of violence against members or the gang itself: at paras. 5, 15.

[22] In R. v. Liu, 190 C.C.C. (3d) 233, the Court of Appeal for Ontario upheld the trial judge's decision to admit opinion evidence from an expert in Chinese culture about the meaning and significance of Chinese characters written in blood on a cloth found near the deceased. Without the expert's evidence, the court found that the "cultural significance of the letter would have been lost on a Canadian jury": at paras. 20-21.

Issue 1: Is Dr. Bélanger Qualified to Give Expert Evidence?

[23] Dr. Bélanger describes herself as a social scientist because of her multidisciplinary background. She studied communications at the undergraduate level, has a masters in sociology, and holds a PhD specializing in social demography. While her academic and scholarly work has focused in Vietnamese and Asian studies, she has also developed an expertise in migration issues, including foreign workers. She speaks several languages including Vietnamese. She is presently a full-time professor at Université Laval and a Senior Canada Research Chair in Global Migration Processes (level 1).

[24] Dr. Bélanger has published on her own or with co-authors over 60 peer reviewed books and/or articles, conducted field research in Vietnam and in countries to which Vietnamese people have migrated, presented at numerous conferences and seminars, received numerous grants and awards, and testified before various Canadian governmental committees on issues related to migration and foreign temporary workers. She is a member of multiple academic associations. The fact that she has not specifically published a paper on a specific topic and relies on the scholarly works of other academics on related issues does not undermine her expertise in these areas. For example, Dr. Bélanger pointed out that on the issue of gendered insults, she relies extensively on the work of Nicolas Lainez who has done extensive ethnographic research on the issue of mother daughter relationships and how insults are used as ways of seeking compliance in daughters. As Dr. Bélanger rightly pointed out, it would be impossible for any person to be able to publish on every single subtopic that might arise within a cultural and family context.

[25] In addition, I find that the fact that many of Dr. Bélanger's published works are conducted in collaboration with other academic scholars, and in particular Vietnamese academic scholars, enhances the reliability of her specialized knowledge.

[26] Defence seeks to qualify Dr. Bélanger to give opinion evidence on the following four specific areas of expertise:

a. Vietnamese family structure and dynamics. This would include intergenerational relations and care, familial expectations and roles including between parents and children and siblings, marriage, and the role of the state and family.

b. Vietnamese gender dynamics. This includes cultural preferences for sons, sex selective abortions, differential treatment of sons and daughters, and the status of adult single women in Vietnamese society.

c. Internal and international migration of Vietnamese women. This includes a daughter's duty towards their parents, factory daughters, and the marriage of and labour migration of daughters to support parental care.

d. International migration and integration of Vietnamese people into Canadian society.

[27] During the voir dire, Dr. Bélanger reviewed the research she has done in each of these subtopics and the specific publications she has authored or co-authored that demonstrate her specialized knowledge in these areas.

[28] In this case, we have heard evidence that members of the Lam family spoke Cantonese, one of the languages spoken in China. In addition, Cst. Tang testified he saw a Chinese calendar on the kitchen wall of the Lam residence. Dr. Bélanger explained that because China occupied what is now the territory of Vietnam for almost 1000 years, there has been a lot of migration of Chinese people into Vietnam and this migration has continued even after Vietnamese independence. Consequently, there are many people of Chinese origin living in Vietnam which has resulted in a blend of the two cultures. Dr. Bélanger explained that it is not unusual for members of Vietnamese families with Chinese roots to speak both Cantonese and Vietnamese and depending on their level and time period of schooling, to speak more of one than the other.

[29] Dr. Bélanger explained that many of the Vietnamese family and social mores on which she proposes to give opinion evidence are not only found in Chinese culture, but in fact are rooted in Confucianism which was imported into the Vietnamese culture during China's occupation. In short, this integration of the Chinese and Vietnamese culture has been accounted for in Dr. Bélanger's work and the study of the Vietnamese culture.

[30] Crown counsel raised concerns about the scope of Dr. Bélanger's expertise and the risk that she would stray into areas on which she is not expert. Crown counsel queried her about her expertise in areas such as Vietnamese views on police, law enforcement, and corruption following her response to certain question asked by defence counsel. For example, defence counsel questioned Dr. Bélanger on how Vietnamese people view police in Vietnam. Dr. Bélanger's response to the specific question was based in part on her own experience and observations of police during her many trips to Vietnam rather than scholarly work in this field.

[31] One need not have been previously qualified as an expert in court or other contexts; it is but one factor: Siddiqi at para 41. Furthermore, I note that Dr. Bélanger has been called upon to testify at various committees on some of her areas of experience. More importantly, Dr. Bélanger explained in cross-examination that in responding to the question, she had qualified that the subject of policing and corruption was not an area of expertise. Nonetheless, while it has not been the focus of her scholarly work, she does have some specialized knowledge about policing and corruption in Vietnam and its impact on the family. She provided examples of how these issues can impact registration for a child in a good school, getting a job, or obtaining a visa to migrate abroad. Consequently, I am satisfied that Dr. Bélanger is aware of her responsibilities as an expert and will abide by any parameters set out by this Court on the permissible scope of her opinion evidence.

[32] Finally, Dr. Bélanger has indicated in writing and orally that she understands and is willing to fulfill her duty as an expert which requires her to provide to the court evidence that is impartial, independent, and unbiased.

[33] Upon review of her curriculum vitae, hearing her testimony, and upon consideration of counsel's submissions, I find Dr. Bélanger has the specialized knowledge gained through study and experience to opine on Vietnamese society, gender, family, and migration and more specifically the subtopics identified: see Mohan, at para. 27.

Issue 2: Is the Proposed Opinion Evidence Logically Relevant?

[34] In this case, there is evidence from the 911 call, the police interviews of the Lam sisters, Chau's testimony, and the testimony of her brothers that both the Lam sisters were subject to verbal and physical abuse throughout their lives and that this violence escalated in the months preceding their mother's death. The nature, duration, and scope of the abuse suffered, including during the time leading up to the offence, will be for the jury to determine upon consideration of the totality of the evidence presented.

[35] Chau testified that notwithstanding the abuse, she continued to care for her mother because it was her duty to do so. She testified about why she did or did not consider particular options to address the abuse she and her sister were experiencing.

[36] I find the proposed opinion evidence is logically relevant to the issue of credibility, motive, intent, and the defence of self-defence should it go before the jury.

[37] The defence of self-defence is set out in s. 34(1) of the Criminal Code, R.S.C. 1985, c. C-46 which states that a person is not guilty of an offence if:

(a) they believe on reasonable grounds that force is being used against them or another person or that a threat of force is being made against them or another person;

(b) the act that constitutes the offence is committed for the purpose of defending or protecting themselves or the other person from that use or threat of force; and

(c) the act committed is reasonable in the circumstances.

[38] A modified objective test applies to assessing the "reasonable" person under the first and third component of the test in ss. 34(1)(a) and (c): R. v. Khill, 2021 SCC 37, [2021] 2 S.C.R. 948, at para. 54.

[39] Reasonableness is not measured from the perspective of the hypothetically reasonable person, but contextualized so that the accused's beliefs are assessed from the perspective of an ordinary person who shares the attributes, experiences, and circumstances of the accused where those characteristics and experiences are relevant to the accused's beliefs and conduct: Khill, at paras. 54, 57. In this regard, consideration will have to be given to the Lam sisters' lived experiences which may, in turn, be informed by the cultural and family mores under which they were raised and continued to operate even following their migration to Canada.

[40] In addition, under s. 34(1)(c), the trier of fact is required to consider a list of non-exhaustive factors set out in s. 34(2) to determine whether the accused's conduct is reasonable. The s. 34(2) factors include:

(a) the nature of the force or threat;

(b) the extent to which the use of force was imminent and whether there were other means available to respond to the potential use of force;

(c) the person's role in the incident;

(d) whether any party to the incident used or threatened to use a weapon;

(e) the size, age, gender, and physical capabilities of the parties to the incident;

(f) the nature, duration, and history of any relationship between the parties to the incident, including any prior use or threat of force and the nature of that force or threat;

(f.1) any history of interaction or communication between the parties to the incident;

(g) the nature and proportionality of the person's response to the use or threat of force; and

(h) whether the act committed was in response to a use or threat of force that the person knew was lawful.

[41] If the defence of self-defence is put to the jury, the proposed expert evidence on Vietnamese cultural and family mores may provide relevant evidence to understand the nature of the relationship between the Lam sisters, the available responses to them as daughters, and the reasonableness of their perceptions as it related to the apprehension of harm. This evidence is relevant to understand the state of mind of the Lam sisters which is a relevant consideration in the elements of homicide as well as aspects of the defence of self-defence. As defence explains, it is being tendered for the subjective mindset of Chau and/or Hue and not to suggest that there was a cultural defence for the killing itself.

[42] As discussed in R. v. Lavallee, [1990] 1 S.C.R. 852 and jurisprudence that followed thereafter, there are many widespread stereotypes about why women stay in abusive relationships or fail to report abuse. Expert opinion evidence on Battered Wife Syndrome has been admitted in cases to assist triers-of-fact in addressing those stereotypes so as to better understand the reasonableness of the accused's apprehension of harm and their responses. Stereotypes abound in cases of domestic violence and can directly impact a jury's assessment of the credibility of victims of violence. People are apt to question why a person would not leave a relationship if abused or assume the abuse is not as bad as they describe because otherwise surely, they would have left. Similarly, it is not commonly understood why a person may be reluctant to report the abuse to police, family, or friends: R. v. Mallot, at paras 42 and 43.

[43] Similarly, in this case the proposed expert evidence may assist the trier of fact in assessing why the Lam sisters, who were adult women aged 56 and 60, would remain in an abusive relationship with their mother. More specifically, the proposed expert evidence may assist the jury in understanding how culturally informed and internalized notions of shame, duty, obedience, sacrifice, filial piety, family hierarchy, and karma could have impacted the Lam sisters' perception of events and their options. Some examples identified by defence include Chau's explanation that she could not:

• be "insolent" or fight back with her mother;
• call the police and report their mother's abuse;
• seek help from other family or Vietnamese community members;
• remain permanently in Vietnam when she and her sister went there for a visit to assist with her sister's depression;
• provide details of the abuse to her brothers;
• have her brothers' families take over the care of their mother; and
• resist her eldest brother's request to have their mother return home after three days in long-term care.

[44] Amicus curiae for Hue highlights how the cultural and family mores may also help the jury understand Hue's statements to Det. Séguin following her arrest. For example, in her statement to the police, Hue talks about the fact that her mother's control over her extended having to seek permission even as an adult to leave the home. That type of relationship with an adult and their parent would not be understood by a Canadian juror. She also discussed why she would be too ashamed to speak of her mother's abuse to others. In addition, in their statements to the police both Hue and Chau Lam were reluctant to acknowledge their brothers and/or allow the officers to contact them. Dr. Bélanger's opinion evidence as it relates to roles of sons and daughters within the Vietnamese family and the relationships and expectations as between siblings may facilitate the jury's understanding of those responses.

[45] Furthermore, cultural and family mores about respecting one's parents, including after their death, may assist the jury in assessing Chau's reluctance to speak of her mother's abuse towards her and her sister upon arrest and at trial. It may also assist the jury in understanding some of the Chau's statements during her testimony. For example, during cross-examination, Chau testified why she made certain statements to Det. Brennan and stated: "Afterword what I did was wrong and wanted to take responsibility for everything and repay my mother and repay the debt to my mother." The concept of repaying a debt would not make sense to the average juror. However, as Dr. Bélanger explained, these remarks may be rooted in the concept of one's continuing duty of care and respect for a parent even after death.

[46] In addition, Dr. Bélanger's opinion evidence can educate the jury on the meaning and impact of gendered insults. There is evidence from various witnesses that the deceased verbally abused both Chau and her sister. For example, Chau testified that her mother called her a "whore" and a "prostitute" and told her she had an "itchy cunt" and that even if she took her pants down on the street, nobody would want to "f… her." In addition, when describing the verbal abuse to Det. Séguin, Hue Lam told him that the deceased used words like "spinster" which was a very bad word in the Vietnamese language. Hue also discussed how the deceased shamed her when she was no longer able to work after she became ill with Parkinson's disease.

[47] While the derogatory nature of the above-noted insults may be evident to members of the jury, it would not be within the average juror's knowledge to understand precisely what these gendered insults mean in Vietnamese society, the shame associated with them, and what impacts they can have when made to children, particularly daughters. Dr. Bélanger's opinion evidence on gendered insults and the role of daughters and marriage in Vietnamese society would educate the jury on these issues and could also facilitate their understanding of the conflicting evidence the jury has heard on the issue of expectations and views on marriage within Vietnamese society.

[48] In conclusion, I find the evidence is logically relevant to the issues at trial which includes credibility of witnesses, motive, intent, and elements of self-defence should it be put to the jury.

Issue 3: Is the Evidence Necessary?

[49] It is clear upon reviewing the cultural context report prepared by Dr. Bélanger dated June 15, 2025, and upon hearing her testimony in the voir dire on Vietnamese cultural and familial norms that Dr. Bélanger possesses specialized knowledge about Vietnamese cultural and family mores that go well beyond what a jury would know about the subject. Therefore, Dr. Bélanger's opinion evidence is necessary to assist the jury: see Mohan, at p. 23.

[50] In addition, as Dr. Bélanger explained, her specialized knowledge accounts for the blend of Chinese and Vietnamese culture resulting from the migration of Chinese immigrants into Vietnam. Consequently, she is well positioned to provide opinion evidence on Vietnamese cultural and family mores notwithstanding that the Lam sisters are part of a Chinese family that migrated to Vietnam and then to Canada.

[51] As already noted, this evidence relates to central issues at trial, including the credibility of the witnesses. I have considered the jurisprudence filed by Crown and disagree that in these circumstances, this is a case where a jury instruction that they must keep in mind that people come from distinct cultural and familial mores would be sufficient: R. v. D.D., 2000 SCC 43, at paras 64 to 68; R. v. A.K., [1999] O.J. No. 3280, at paras 91-93; and R. v. Meecham, 2019 ONSC 494, at paras 38-40. Domestic abuse within the family context is complex and subject to stereotypes: J.M.M. v. C.R.M., 2025 ONSC 3067, at paras 291-292. As discussed further below, I find that the absence of cultural context evidence risks resulting in an unfair trial.

Issue 4: Does the Proposed Evidence Meet the Remaining Threshold Factors?

[52] The proposed opinion evidence is not subject to an exclusionary rule.

[53] As already discussed, expert evidence about cultural context and mores within communities is a well-recognized field of study within academic and professional disciplines and has been admitted in multiple cases: Shafia, at para. 240.

Issue 5: Is the Expert Evidence Sufficiently Beneficial to the Trial Process to Warrant Its Admission?

[54] In the final stage of the analysis, the trial judge must exercise their gatekeeping function and be satisfied that the benefits of admitting the evidence outweigh the costs of its admission. As stated by Boswell J. "this is an assessment about whether the evidence is 'worth the candle'": R. v. Osborne, 2019 ONSC 907, at para. 58.

[55] The requirements of the gatekeeping function are aimed to ensure that expert evidence is not routinely admitted with only its weight to be determined by the trier of fact: Abbey 1, at paras. 78-79; White Burgess, at para. 20.

[56] The four factors of legal relevance, necessity, reliability, and absence of bias continue to play a role in weighing the overall competing considerations in admitting the evidence. These factors must be measured against potential prejudicial effects such as consumption of time, prejudice, and confusion: White Burgess, at paras. 24, 54.

[57] For the same reasons outlined above, Dr. Bélanger's proposed opinion evidence is necessary to provide the jury with knowledge about Vietnamese cultural and familial norms that is not within the purview of the average juror so that they can better understand the testimony of the witnesses in this case and the accused's evidence as per their police statements. Concepts of filial piety, duty, shame, and honour as they apply generally in Vietnamese society, and more specifically to daughters within Vietnamese society, is knowledge outside the scope of a Canadian jury. The proposed expert evidence on these concepts will facilitate the jury's ability to understand the accused's state of mind and perception of events. It is relevant to the issues of credibility, motive, intent, and the defence of self-defence should it go before the jury.

[58] Crown counsel has raised concerns that opinion evidence may be introduced that will relate to issues that lack an evidentiary basis. However, this issue goes to weight rather than admissibility. At this stage, I must simply be satisfied there is some evidence on the issues in question for which expert opinion evidence may be relevant. Defence has provided, as set out above, evidence already before the jury for which cultural context evidence may be relevant.

[59] While Dr. Bélanger did interview both the Lam sisters, defence is not seeking to have her opine on specific statements she made to them about their views and conduct, but to provide cultural context evidence that will allow the jury to evaluate for themselves the evidence the Lam sisters presented at trial, be it through their viva voce testimony or their police statements. While Dr. Bélanger did interview the Lam sisters and their brother Chanh Huynh to identify the cultural and familial mores that might be at play and determine if she has relevant opinion evidence to give, defence is not intending to elicit from her what statements they made to her or her opinions about them. Therefore, I find the probative value of the evidence is outweighed by any risk of prejudice as it may relate to this concern raised by the Crown.

[60] I find that Dr. Bélanger is qualified and her proposed opinion evidence is reliable for the purposes of admissibility. Threshold reliability for the purposes of admissibility is distinct from ultimate reliability that will have to be assessed by the jury upon hearing the totality of the evidence and determining what weight, if any, they wish to give to the opinion evidence in explaining the conduct of the Lam sisters. For example, they may find that the Lam sisters' reluctance to discuss their mother's abuse is rooted in cultural or familial mores about respect for the dead or they may find that cultural or familial mores have no bearing on this issue. Those considerations will be for the jury to decide upon hearing the whole of the evidence and upon proper instruction on the use and weight to be given to opinion evidence.

[61] I find there is a risk that without the proposed expert evidence, the jury may be misled by stereotypes resulting in an unfair trial. If we have learned one thing from the jurisprudence and literature on domestic violence, it is that people's behaviours and responses to violent interactions may vary. Where those responses are informed by deeply entrenched cultural and family mores, we risk falling into stereotypes which may result in unfairly undermining the credibility of some witnesses while bolstering the evidence of others resulting in an unfair trial: An example of this was set out in R. v. B.G., 2022 ONCA 92, at para 34.

[62] For example, in R. v. B.G., the appellant was convicted of sexual offences against his daughter. The complainant was born in Canada but spent the first three years of her life in India raised by her grandparents and other family members. At the age of 31, the complainant reported to the police that the appellant, her father, had sexually abused her from the ages of 6 or 7 to 14. The main issue on appeal was whether the Crown had invited the jury to rely on impermissible racial or cultural stereotyping in the cross-examination of defence witnesses and in statements made during their closing address. Defence did not object when reviewing the charge to the jury or seek a cautionary instruction that the jury should not infer that because the witnesses were Indian women, they were governed by traditional Indian norms, and as a result, culturally conditioned to submit to the domination of men, tolerate physical and sexual abuse by the family patriarch, and lie about it under oath to protect family honour.

[63] In addressing the issue, the Court of Appeal for Ontario discussed the fact that the norm of a particular culture is a question of fact which is to be resolved according to evidence led at trial, including through expert evidence if it is not a matter of everyday experience of the average person. The court stated the following about cultural evidence at paras. 11-12:

An ethnic or national culture consists in part of shared beliefs and norms, social institutions, and patterns of behaviour. It can include duties and obligations, and other beliefs about what ought to be done and not done, and what constitutes a good life. The norms of any particular culture is a question of fact to be resolved according to evidence led at trial, including expert evidence if not a matter of everyday experience of the average person: R. v. Shafia, 2016 ONCA 812, 341 C.C.C. (3d) 354, at para. 241.

Where relevant to a matter in issue, it is permissible for the trier of fact to consider whether the beliefs and practices of a particular culture provide some evidence about what a particular person believes or explain that person's apparent behaviour: R. v. Boswell, 2011 ONCA 283, 277 CCC (3d) 156, at paras. 25-26; R. v. S. (R.D.), [1997] 3 S.C.R. 484, at paras. 124, 128-30, 133, per Cory J. It is, however, impermissible to invite the trier of fact to adopt a stereotype about cultural practices unsupported by evidence and use it to draw conclusions about a witness's beliefs or actions.

[64] Ultimately, the Court of Appeal found that the frequent references to cultural norms, more specifically traditional Indian norms, by the Crown in both the questioning of witnesses and its closing address resulted in an unfair trial.

[65] While cultural evidence need not be called in all cases, knowledge about cultural and family mores may help a jury unpack and better understand a witness's behaviour. In this case, counsel have repeatedly questioned the various witnesses on their adherence to Vietnamese cultural beliefs and practices. I find that in these circumstances, opinion evidence is necessary to ensure a proper understanding of the cultural norms being adhered to, and its absence in the circumstances of this case, may very well result in an unfair trial: B.G., at para. 34.

[66] I am also not persuaded that there is a risk that proposed opinion evidence will usurp the jury's fact finding role: R. v. Sekhon, 2014 SCC 15, [2014] 1 S.C.R. 272, at para 46. The purpose of evidence is to educate the jury about Vietnamese cultural and family mores. It will be for them to decide what weight, if any, should be given to this opinion evidence. It will also be for the jury to decide if cultural and family mores assist them in understanding the testimony of the witnesses and could have had any application with respect to the conduct and responses of the Lam sisters. Furthermore, as already noted, counsel will not be asking Dr. Bélanger to opine on the specific statements and conduct of the accused. Any remaining concerns of prejudice can be dealt with by way of jury instruction.

[67] The additional expert evidence will require another day or possibly two days of trial and will prolong the length of trial. It may also require more elaborate jury instructions. Nonetheless, I find the opinion evidence is necessary and has probative value that far outweighs these particular risks of prejudice.

[68] Having reviewed the expert report and having heard the evidence on the voir dire, and considered the submission of counsel, I find the probative value of the evidence is not outweighed by any prejudicial effect. In undertaking the cost-benefit analysis on the admission of the opinion evidence, I have considered again the threshold factors of relevance, necessity, reliability, and whether or not there is any bias in the proposed evidence. Having weighed the factors against the consumption of time this evidence will take, whether the evidence might confuse the jury, and any other potential prejudice, I find the probative value of the evidence is not outweighed by any prejudicial effect.

Conclusion and Parameters

[69] In conclusion, Dr. Bélanger is permitted to testify as an expert on Vietnamese society, gender, family, and migration and more specifically, to provide opinion evidence on the subtopics outlined at paragraph 26.

[70] I appreciate that the term "Vietnamese society" is a broad term and may result in Dr. Bélanger straying into opinion evidence on aspects of Vietnamese society that may overlap but are not necessarily the focus of her scholarly work. One illustration of this arose with respect to questions about the views of Vietnamese people on policing and law enforcement and the issue of corruption within Vietnam. Consequently, Dr. Bélanger will not be permitted to opine on those areas except to the extent that they form part of her specialized knowledge of Vietnamese gender, family, and migration. If a question is to be asked about policing and law enforcement, defence will provide the question to Crown in advance so any potential conflict can be resolved before Dr. Bélanger testifies.

[71] Furthermore, as a cautionary measure, if either party intends to ask Dr. Bélanger questions outside of the four subtopics of expertise and these questions did not form part of the questions put to her in voir dire, counsel will share the wording of those questions with the opposing party. If there is any dispute about the subject matter to be introduced, the parties must raise it before Dr. Bélanger is to testify so that the conflict can be resolved.

[72] This direction does not preclude me, as gatekeeper, to disallow any questions even in the absence of an objection from the opposing party.

[73] Finally, should there be any discrepancy between the written and oral decision, the written decision shall prevail.

Somji J.

Released: August 5, 2025