Proulx appeared in court in Rivière-du-Loup Monday on charges of sexual assault, break-and-enter, armed robbery and committing an indignity to a human body.
He was sentenced to five years in prison on each charge, to be served concurrently with his life sentence for Michaud's first degree murder.
Proulx also let it be known he would not seek leave to appeal his May 2009 murder conviction to the Supreme Court of Canada.
The Quebec Court of Appeal rejected his request for a new trial last July.
Nancy Michaud, the mother of two children, worked as a riding assistant for the late Claude Béchard, then Liberal MNA for Kamouraska-Témiscouata and natural resources minister.
Michaud was killed on May 15, 2008 in Rivière-Ouelle, a village in the Lower Saint-Lawrence region, about 140 kilometres northeast of Quebec City.
Proulx was arrested a few days later.
During his trial, Proulx confessed to killing Michaud. But his lawyers argued he should not be held criminally responsible for the crime. They said his mental state, triggered by the effects of the antidepressant Effexor, rendered him incapable of understanding the consequences of his actions.
Proulx is serving a life sentence with no possibility of parole for the first 25 years.