Organizers of L.G.B.T. Pride festivities in Toronto voted this year to bar the police indefinitely from their parade. In Minneapolis, the police decided not to march, citing community opposition to their presence. And Vancouver Pride organizers in British Columbia said officers could march alongside city employees such as librarians and park workers, but only if they left their uniforms at home.

Uniformed police officers were barred from marching in Sacramento and St. Louis until organizers in both cities reversed their decisions after criticism from law enforcement groups and others. And L.G.B.T. activists in New York plan to shun official Pride events this weekend in favor of an alternative march that will exclude police officers and corporate sponsors.

“This is where the movement is heading, and it is happening nationwide,” said Sayer Johnson, executive director of the Metro Trans Umbrella Group, the nonprofit that will serve as grand marshal of St. Louis’s Grand Pride Parade on Sunday. “Whether or not people want to pay attention to it, this is where we are going.”

Mayor Lyda Krewson of St. Louis said in a statement that officers belonged at the Pride parade because “exclusion of the Police Department, or of anyone, is not in the spirit of our city.”