PARRY SOUND, ONT. -- At the O'Leary boat crash trial in Parry Sound on Friday, the courtroom heard from an OPP officer who recalled being frightened during a crash reconstruction on Lake Joseph.

Const. David Hogue testified the reconstruction exercise involved two boats, one without its lights on, in the dark to simulate the events of the fatal collision.

Hogue told the court being at the helm of the OPP Harbour Craft was "nerve-racking" as it approached Dr. Irv Edwards' vessel in the darkness.

"Even though we knew it was there, it was shocking to see how close we were to it before noticing it," he said.

Court heard the OPP boat was travelling between roughly 24 and 35 miles per hour during the exercise.

The defence, led by lawyer Brian Greenspan, suggested the O'Leary boat may have had speeds of around 19 miles per hour.

O'Leary was captaining her boat with her husband, reality tv star Kevin O'Leary in the back alongside friend Allison Whiteside.

The trio was returning from a dinner party on the lake at the time of the crash - about four minutes after departing from their friend's nearby cottage.

Over the first two weeks of the careless boating trial, court heard conflicting witness testimony over whether the boat carrying 12 stargazing passengers had its lights on when it was struck by the O'Leary boat.

Witnesses from the O'Leary cottage said they were looking out on the water at the time of the crash. O'Leary's son Trevor and his friends and girlfriend testified they did not see the Edwards boat's lights turn on until after the collision.

Edwards and his friend, Dr. Richard Ruh, who was captaining the boat at the time, testified the lights were on. Both men are being sued in civil court. Ruh was charged and convicted for failing to display his stern light.

The court heard O'Leary was provided with a drink of vodka and sparkling water at the dinner party. Witnesses said they did not see her consume the beverage.

Witness testimony from a family friend said O'Leary asked for someone to get her a drink to calm her nerves after the crash to calm her.

Two hours after the collision, O'Leary provided a breath sample to police which produced an alert reading. Her licence was suspended for three days.

Gary Poltash, 64, and Suzana Brito, 48, died from head and neck injuries sustained while sitting at the front of the Edwards boat.

Three officers who participated in the reconstruction investigation will testify Monday.

Closing submissions are expected Thursday. The judge's decision could take several weeks.