But Liberal leader Denis Napthine warned Ms Nixon was making a mistake.

"The police commissioner should be above these sort of activities," he said. "It undermines the value of the police uniform as a sign of authority and respect."

And Nationals leader Peter Ryan said Ms Nixon's decision was a terrible precedent she would come to regret.

Premier Steve Bracks said Ms Nixon had to best judge how she could represent and be involved with all sections of the community.

Gay and Lesbian Police Employees Network member Acting Supt Jill Wood said the move marked a turning point in relations between the force and the gay community and gay police.

"I think it's a wonderful occasion for us and something that makes me very proud to be a member of the police force. And I think that it shows the chief's commitment to the principal of diversity," she said.

But Acting Supt Wood said she did not think a public apology to gay police was needed.

Ms Nixon was asked last week by GALPEN members whether she would lead them in the march through St Kilda in January and allow them to wear police uniforms.

Police previously have been refused permission to wear their uniforms while marching under the GALPEN banner.

Ms Nixon yesterday said she was pleased to march with gay officers in uniform.

"I'm determined to support all members of Victoria Police and provide encouragement and leadership, to ensure that all members are recognised and valued across the organisation," she said.

"I come from a state where police marching in the Mardi Gras parade has happened for the last number of years, and more recently in uniform, and some of those police were gay and lesbian members and some were just supporting their colleagues."

As a NSW assistant commissioner, she attended the Sydney Mardi Gras to take the salute from participating officers.

"I simply see it as a way of supporting members who asked me to do so," Ms Nixon said. "They feel that they have been incredibly alienated.

"They try to do their work with the gay and lesbian community and they have been trying to identify some of the issues within the community, within Melbourne and within Victoria."

March president Penny McDonald said Ms Nixon's presence was a coup and would help attract more people to the event.

"It's a very public show of a shift in police policy and attitudes towards gays and lesbians and gay and lesbian police officers in their own workplace," she said.