The appellant bank loaned money to the respondent's wife, secured by a mortgage and guaranteed by the respondent.
When the mortgage matured, the bank and the mortgagor renewed it at a higher interest rate without notice to the respondent.
The mortgagor defaulted, and the bank obtained summary judgment against both.
The Court of Appeal set aside the judgment against the respondent, finding he was released from the guarantee.
The Supreme Court of Canada dismissed the bank's appeal, holding that the renewal agreement constituted a material alteration of the principal contract without the surety's consent, thereby discharging the guarantor.