A former youth soccer coach accused of trying to arrange a sexual offence against an 11-year-old girl was found guilty on all charges by a judge Tuesday morning.

Wesley Vander Leeuw was accused of arranging through telecommunications to commit a sexual offence against a child and child pornography offences from 2015 and 2016.

Police say they first received a tip in 2016, which prompted an undercover officer to create an online persona, "Shannon," to message Vander Leeuw.

According to investigators, Vander Leeuw believed he was talking to a girl and her mother, and that he sent sexually explicit messages like, "How do you want your daughter to learn about sex?" and "What would you like to have done or see done?"

Over his five-day trial, Vander Leeuw and his lawyer argued he had made a Craigslist ad inviting other adults to a hot tub party. Through the ad, Vander Leeuw says he became concerned by a woman who he thought may be abusing children, and that he sought to find more evidence to submit to police.

On Tuesday, Justice Michael Lema said he found Vander Leeuw's reasoning non-credible.

"His overall account was implausible. He was not a crime investigator in any sense," Lema said in court.

"He was on anything but a child-protection investigation."

Vander Leeuw was also charged with possessing child pornography, related to the words he wrote in the online and text messages.

Vander Leeuw is currently out on bail, will be until he is sentenced. A date for a sentencing hearing is expected to be set by the end of this month.

With files from Bill Fortier