Crown attorney Sylvain Petitclerc says Brazeau will be released Wednesday into the care of a rehabilitation facility in Sherbrooke, Que.
Brazeau faces three charges — two related to being behind the wheel of a car while impaired, and a third for possessing a weapon in breach of his bail conditions.
Petitclerc says he'll remain in rehab until Dec. 8, the date of his next court appearance on the latest charges, but his therapy may continue for up to two years.
The senator spent the night in custody after a police officer who spotted Brazeau alone in a car reported smelling alcohol on his breath and finding a knife in the car.
Gatineau police spokesman Const. Pierre Lanthier says Brazeau was arrested after he blew twice the legal limit during a roadside breathalyzer test. Police say he also failed a second breathalyzer test at the police station.
The car has been impounded for 30 days, and Brazeau's licence has been suspended for 90 days.
Lanthier said he didn't know if the car belonged to Brazeau or to someone else.
This is Brazeau's second trip to rehab in recent months. Earlier this year, he completed a stint at a rehabilitation facility in the Quebec municipality of Saint-Andre-d'Argenteuil, which is located along the Ottawa River just south of the town of Lachute.
That trip resulted from his arrest in April, when he was charged with assault, possession of cocaine, uttering threats and breaching bail conditions following an altercation involving a man and a woman at a home in Gatineau. He has pleaded not guilty to those charges.
One of the conditions of his release from custody in April was that he not possess any weapons.
Brazeau also faces charges of assault and sexual assault in relation to a separate incident from February 2013 that got him booted from the Conservative caucus. He will stand trial for those charges in late March 2015.
He also faces charges of fraud and breach of trust in connection with his Senate expense claims.
Last year the Senate ordered Brazeau to pay back almost $50,000 over disputed expense claims. He refused and the Senate garnisheed his salary until last November, when he was suspended without pay.
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Note to readers: This is a corrected story. An earlier version included an incorrect spelling for Sylvain Petitclerc's surname.
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