Mandeville was also convicted of breach of recognizance April 4, again for smoking marijuana, and given two years probation.
Because he is considered a threat to public safety, his probation has 28 conditions, including not consuming illicit drugs and submitting to urine tests.
On April 10, he was arrested by RCMP after testing positive for marijuana.
Mandeville pleaded guilty to the charge.
Crown prosecutor Alex Bernard asked for three to six weeks incarceration.
Defence lawyer Glen Boyd said Mandeville smoked the drug because he was "stressed out" by the media coverage about him.
Boyd said after Yellowknifer published articles about Mandeville, he was threatened.
When given a chance in court, Mandeville declined to comment.
While committing a sex offence in 1993, Mandeville was under the influence of hashish and marijuana, said Bernard.
Territorial court judge Brian Bourassa told Mandeville the complexity of the case requires him to abide by the conditions.
"The accused is going to have to understand he has to comply regardless of pressures or other events," said Bourassa.
"There is no room to negotiate."