When I came out of the Quantico US Marshal Academy in 1965, we graduated with our service weapon which was a Model 13 with a six and 1/2" long barrel.
We were trained to use this barrel as a baton.
But as an Air Marshal in a Brooks Brothers suit and tie, never got a chance to use this technique. Took a few years to get enough time in to get on a FA Team.(fugitive apprehension), which all training got applied in real arrests.
Batons were only issued when protecting a Federal Judge in court proceedings, which was our major job description.
For office duty doing paper work, a Model 10 3"barrel, was carried under our suit coat in a belt holster. Suit and tie was mandatory at all times.
And yes,, I still have my "office" three inch.