Mark Gordon was sentenced to two concurrent life sentences, with no eligibility for parole for 21 years, after pleading guilty in 2025 to two counts of second-degree murder, according to court reporting from the sentencing hearing.
Andrieana Montgomery, 42, and her former husband Robert Patrick Montgomery, 41, both teachers, were shot on July 13, 2024, at homes on Glenforest Street in Oshawa, the reporting says. Andrieana Montgomery taught at Bowmanville High School and Robert Patrick Montgomery taught at All Saints Catholic School in Whitby. Gordon had received an eviction notice the day before, which he blamed on Andrieana Montgomery, according to the court account.
Justice Michelle Fuerst imposed the sentences, with the parole-ineligibility period running from Gordon's arrest on July 13, 2024, the reporting says. Thirty-three victim and community impact statements were presented at the hearing.
Gordon used a legally owned handgun, the reporting says. The couple's two sons, then aged 12 and 10, witnessed the aftermath of the shootings, according to the reporting.
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Sources & publication details
- Byline
- Daily Durham News
- Published
- Oct 30, 2026, 2:41 p.m.
- Source
- www.durhamregion.com
