WINDSOR, ONT. -- A key witness in the manslaughter trial of Windsor’s Michael Hiller testified to an angry encounter between the accused and the late Joe St. Louis, a former Lakeshore district fire chief.

On Tuesday, Mary Botosan took to the stand in Superior Court to outline her account of what happened between her then-husband Hiller and St. Louis on March 24, 2018.

The 45-year-old Hiller is charged with manslaughter and assault in the death of St. Louis, who died on March 29, 2018.

Court heard the fatal encounter was preceded by a night of drinking. First, St. Louis met Botosan at an establishment the pair would frequent often before leaving together to a second bar.

Court saw video of Botosan, St. Louis and Hiller all at the second bar at the same time on the night of March 23, 2018. The video captures an animated conversation between St. Louis and Hiller before going their separate ways.

Botosan told the court she was in an intimate relationship with St. Louis since August of 2017, but living with her estranged husband at her home on Daytona Avenue in Windsor along with their two daughters.

According to Botosan, when she and St. Louis arrived at her Daytona Avenue home early in the morning on March 24, Hiller yelled at St. Louis from the kitchen while holding a knife. Botosan told court Hiller pushed her down and the next thing she recalls, St. Louis was unconscious on the front lawn.

On Monday, court heard from pathologist Dr. Edward Tweedie, who testified St. Louis died of "irreversible brain damage" caused by a "significant neck compression."

The judge-only trial is set to run three weeks.