Patrick Brazeau will spend the night behind bars.
The suspended senator is charged with five criminal offences following an alleged domestic dispute involving an ex-girlfriend and another man at a Gatineau residence around 4 a.m. Thursday.
Gatineau police allege Brazeau, 39, fought with a woman on a balcony, then had a separate altercation with a man inside the home; investigators say he was found to be in possession of a white powder that could be cocaine.
Sgt. Pierre Lanthier tells CTV they believe Brazeau was under the influence of alcohol at the time.
Brazeau is charged with two counts of assault, uttering death threats, possession of cocaine and breach of undertaking; he pleaded not guilty to all five charges during a brief court appearance Thursday afternoon.
Crown lawyer Sylvain Petitclerc says Brazeau will remain in jail until his next appearance Friday morning.
In February, the RCMP charged Brazeau with fraud and breach of trust in relation to his Senate expense claims.
In another case, Brazeau is charged with assault and sexual assault over an incident at his home in February 2013.