Greene's support for cohabitation law reform placed her in opposition to North York Mayor Mel Lastman, who initially supported her but then attempted to exclude boarding houses from the city. Following an eight-year legal battle conducted by lawyer Barry Swadron QC, on behalf of Doug Bell, a resident of North York who had been charged with living with other people to whom he was not related, the Supreme Court of Canada upheld Greene's position and struck down the municipal bylaw in April 1979.