Joint service color guard squads routinely participate in parades and ceremonies of all kinds like this opening ceremony for the 2013 AT&T National, an annual golf tournament held at the Congressional Country Club in Bethesda, Md.

WASHINGTON — Shortly after Dykes on Bikes rumble across the starting line of the Capital Pride parade in downtown Washington on Saturday, an expected 150,000 spectators should witness something never before seen on an American city street — a U.S. armed forces color guard marching alongside rainbow flags in a gay pride parade.

The Department of Defense has authorized what military gay-rights groups and organizers of the Capital Pride parade say is a first nationwide — a color guard that will present the red, white and blue as well as flags of each branch of the military.

The eight-member team is scheduled to help lead off the 1.5-mile parade, immediately preceding the Capital Pride lead banner and grand marshal Chris Kluwe, the former NFL punter and author of the book "Beautifully Unique Sparkleponies."

While no policy has precluded a U.S. armed forces color guard from participating in gay-rights events since the 2011 repeal of Don't Ask Don't Tell, gay-rights organizations from D.C. to Hawaii say they have routinely faced rejection from local military offices, saying the color guards were otherwise occupied on the days of pride parades.

Lt. Cmdr. Nate Christensen, a Department of Defense spokesman, said he could not confirm whether Saturday's event was a first because decisions about military support for parades are generally made at the local level. Christensen said an Armed Forces color guard did perform on the grounds of the Pentagon last year for a Department of Defense pride event and one was scheduled to perform there again Thursday.

Lt. Col. Todd Burton, a founding member of Outserve, which has tracked the color guard issue and repeatedly sought to win approval for one at a pride event, said Saturday's is a first as far as he knows.

The group that has perhaps most often been rejected is the organizing committee of the Honolulu Pride parade.

Carolyn Golojuch, president of Rainbow Family 808, said parade organizers, including her husband, a retired military officer, have repeatedly been turned down.

"They've said they didn't have a team ready to go, which is a lie because they have a color guard for every Tom, Dick and Henry."

Golojuch said the group had grown tired of rejection and didn't bother asking this year.

In D.C., however, the color guard will be provided by the United States Military District of Washington, which presents colors for the president, members of Congress and countless official state functions.

An approval letter sent to pride parade organizers last month listed one caveat to the team's expected participation Saturday: "Please note this appearance is subject to preemption by the White House or other official military requirements."

Bernie Delia, president of the board of directors for Capital Pride, said he was thrilled to have the color guard participate. He said members of Outserve and other groups warned Capital Pride officials that they might receive a rejection letter.

"We knew we might get turned down, but we asked and they said 'yes,' " Delia said. "I think that's very significant."