Jennifer Pawluck, 22, was found guilty in April of criminal harassment for snapping a photo of the street art and uploading it to Instagram in 2013.
The judge agreed with a joint suggestion that Pawluck receive a suspended sentence, which includes 18 months probation and 100 hours community service.
She is forbidden from using Instagram, Facebook or Twitter for the first year, except to send private messages.
Pawluck is also prohibited from posting anything about police or anyone associated with the judicial system.
Montreal police Cmdr. Ian Lafreniere, a high-profile spokesman and the main public voice of the force during major events, told Pawluck's trial in February that knowledge the graffiti was being shared shook him, scared his children and forced his wife to take a leave from work.
Pawluck countered that she posted the image without knowing who Lafreniere was and said it was meant as a statement against police in general — an argument the judge cast doubt on in finding her guilty.
One of the conditions attached to her sentence forbids Pawluck from contacting Lafreniere or his family.
Prosecutor Josiane Laplante said outside the courtroom she was satisfied with the sentence, noting there was a lack of jurisprudence in the case.
"Social media is still a pretty new phenomenon," Laplante said. "This sentence reflects all the criteria that needed to be addressed, including denunciation and dissuasion."
On Thursday, Quebec court Judge Marie-Josee Di Lallo reminded Pawluck again of the dangers of posting online without thinking, referring to what can happen with "a simple click."
Pawluck told the judge she recognized that fact.
She will have one year to complete the community service as she is returning to school in September to finish her high school degree.
As she was charged under a summary offence, Pawluck faced a maximum sentence of six months in jail or a $5,000 fine.
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