In determining the sentence, Justice Heather Perkins-McVey noted that it was Stanley's first offence, that he pleaded guilty and said she believes he is remorseful and wants treatment, but she also noted there were four victims.
The four boys, who were involved in Scouts Canada, were "scarred" by Stanley's actions, Perkins-McVey said Wednesday, and "will carry these scars with them for the rest of their lives."
Stanley will get credit for time already served in pre-custody and under house arrest, so his actual time in prison will be three years and 281 days.
Incidents involved boys aged 12 to 15
Stanley, 31, was a volunteer with Scouts Canada for five years, beginning in 2009. He is also a former City of Ottawa lifeguard and swim coach.
Stanley pleaded guilty in late June to 10 counts of sexual interference, three counts of luring and three counts of invitation to sexual touching. The incidents began in 2012 and occurred when the boys were between 12 and 15 years old.
The molestation began in the summer of 2012 and continued for a year and a half, according to an agreed statement of facts read during Stanley's sentencing hearing in September.
Stanley took the boys to movies, hosted visits in his parents' basement and drove the boys to secluded locations, court heard.
Stanley told one boy not to tell anyone about the sexual abuse because he would get in trouble, court also heard.
Local leader dismissed for failing to act on warnings
Another scout leader told CBC News he warned the organization that Stanley was spending time alone with boys, despite the "two-deep rule" that requires scouts to always be under the supervision of at least two adults.
He said some of the abuse could have been prevented had the organization heeded his warnings sooner.
An Ottawa group commissioner was dismissed for inaction.
Crown lawyer Suzanne Schriek said Stanley was trusted to look after the boys he later admitted to molesting, and that it's an aggravating factor that can't be overstated. She had asked the court for a six- to eight-year sentence.