Another mystery photo ... identified.
Updated: February 20, 2024

Guy wearing the vest and drawing his six-shooter is William Gould. According to the cast list and plot synopsis shown further down this webpage, Gould played a sheriff.

Still code "Mort 7-21" in the bottom right corner of the above photo.

Other than William Gould, the other players are unidentified.

And we have an answer from author and researcher Merrill McCord:

The mystery film is Buck Jones' THE DESERT OUTLAW (Fox Film Corp., 1924). You are right about Gould. My first clue was that the still code "Mort 7-21" was the exact format Fox Film was using at the time. I immediately checked the index of my book on Fox Film, found the name of Edmund Mortimer, determined he was a 1923-1925 Fox Film director, and started perusing all of Fox Films during that period. I eventually came to the above Buck Jones film that was Mortimer's seventh production at Fox Film. To confirm the film's identity beyond doubt, I found the exact still code on your image on pages 128 and 129 of Buck Rainey's book on Buck Jones' silent era.

Thanks Merrill

  Internet Movie Database (IMDb) has information on THE DESERT OUTLAW:

The above lobby card was found via a Google search. There's Buck Jones and on the ground is William Gould attending an unidentified guy. Note Gould's uniform - same hat, vest, and gunbelt that he's wearing in the top photo.

Cast listing and plot synopsis from Exhibitors Trade Review, available at the Internet Archive. Is William Haynes really William Haines?

Is the guy on the right side of the top photo William Haines? Compare his face with a 1924 photo of William Haines shown on the left.