But the move has angered province's public security minister.
The uniforms include a black cowboy hat emblazoned with a sheriff's badge, and another badge worn on the officer's chest. The badge has the logo of the Châteauguay police officers union on it.
Officers are also wearing cowboy boots on the job, but only until the weather gets colder. They will then return to more seasonal footwear.
Union president FrançoisLemay said the new look will not interfere with the work members do while they're on the job.
"We'll never touch the service to the population," said Lemay. "We [work as officers] with a passion. Police officers are passionate people, and it's not because I'm wearing this [different] uniform that it changes something to our passion."
Public Security Minister Lise Thériault, called Châteauguay mayor Nathalie Simon about the uniforms.
Thériault said the uniforms are unacceptable and the officers have gone too far with their pressure tactics. She called on the mayor to bring the officers to order.
Quebec's federation of municipal police officers is distancing itself from the pressure tactic.
"The goal of pressure tactics is to put pressure on those who make decisions while maintaining service to the public in its entirety," the federation said in a communiqué.
"Unfortunately, we believe the wearing of the sheriff's costume while carrying out the function of a police officer cannot guarantee this fundamental goal."
The new uniform is not leaving people indifferent.
"I find it shows a lack of respect for me as a citizen," said Françoise Théoret. "I find they're spending more time on that than real cases they have to work on."
"They have to give a kind of pressure tactic anyway," said Vince Macri. "I find it's better to have them dressed up as cowboys than not serving the people at all."