LONGUEUIL, Que. -- A Montreal-area police officer was found guilty Thursday of dangerous driving causing the death of a five-year-old boy in 2014.

Nicholas Thorne-Belance was a passenger in his father's car when it was struck by an unmarked police cruiser driven by Patrick Ouellet.

Ouellet's trial last month heard he was travelling at about 110 km/h in a 50 km/h zone when he hit the vehicle carrying the boy. The youngster died a few days later.

Ouellet, a provincial police officer, was on surveillance duty when the crash occurred.

In his ruling, Quebec court Judge Eric Simard concluded there was nothing to justify the risk Ouellet took by driving at such a speed.

Crown prosecutor Genevieve Langlois said the court concluded that Ouellet was driving in an "objectively dangerous" manner and that his conduct differed substantially from what a reasonable police officer would have done under the same circumstances.

She added that the victim's family, who were present in the courtroom, appeared to be satisfied with the result.

"For them, it was an important step that was reached this morning," she told reporters outside the courtroom.

"They feel justice was done and they'll take the time that is necessary to accept the guilty verdict that was rendered this morning."

Ouellet, then 29, had been following a former director general of Quebec's Liberal party at the time of the crash as part of an investigation by the province's anti-corruption unit.

The Crown originally decided to not lay charges but Quebec Justice Minister Stephanie Vallee ordered a new investigation, which resulted in Ouellet being charged.

Ouellet's lawyer said she would appeal the verdict but made no other comment.

Sentencing arguments are set for later this year.