My dad became a Dallas Police officer in 1967 and retired in 1989. He carried a revolver untill the last year when he got a sig. He was plain clothes for about the last 15 or so years and used a M36 and a M65 W/3"barrel.

A funny story he used to tell; when he was fresh out of the academy they partnered him with a grizzled ol' veteren for his training period. Now at that time their old Fords did not have any air conditioning, so on a hot summers night, when all the supervisors weren't looking, they would put a block of ice in the floor board, on the passenger side, and let the fan blow over it. Well, this particular night the "sarge" was riding shotgun and got a little perturbed when his shoes started getting wet from the melting ice. So he pulls out his 45 and shoots a drain hole in the floor. All is well until the next red light when the brake pedal goes to the floor and the patrol car shoots right on through the intersection. It seems the bullet went through the brake line on it's way out. Lucky for them, no one was in the intersection and no one got hurt.

Anyway, back to the subject at hand, I know of at least one Dallas Police Officer that carried a 1911 in 45ACP.