Some collectors or special interest buyers look for LE marked guns. I just buy shooters so I wind up with them. Mostly S&Ws.
I am told the dealer where this was shipped supplied cops in Texas but it is not marked. May have been a personal purchase by an officer. I paid $195 for it about 12 years ago at a Denver show.
I got this from a wholesaler in 1989 for $189. They had a bunch of them and they were advertised as police turn ins but it is not marked and I have no idea which agency used it.
No question about this one's heritage. Factory inscribed Utah Highway Patrol it is one of 50 (#27) sent to that agency. I bought it about 5-6 years ago and I know I paid too much for it (rare for me to admit that being a famous cheapskate and finder of good deals) but it was something that I just wanted... badly. I paid $3,000 for it.
A rare 4" pre-war Heavy Duty shipped in 1940 to the Ft. Smith, Arkansas PD. Was blue, someone plated it. Not stamped but letters as shipped to the PD. Bagged it at a local gun show 3-4 years back for $400. Even had the letter with it. Probably too much given the condition, but I live in AR and this is the only gun I have with AR LE history.
A genuine original nickel plated LE revolver. Shipped to the Florida Highway Patrol in 1977 (photo tag says 75 but it was 77). I bought it as police surplus in 1988 for $215. I believe it was in unfired condition when I got it. Must not have ever been issued. One of my favorite (if not THE favorite) pistols.
Bought this at a gunshow in Utah around 2000. Lettered as shipped to the campus police at "Louisiana University" (LA State or U. of LA?). This one looked like new and I paid $165 for it.
Both shipped in 1949. One went to a police officers' private club in Los Angeles and the other to a police supply house in NYC. I figure both were personal purchases by cops for off duty carry. Found them 3-4 years ago one month apart at a local gun show. Paid $200 and $210 (could NOT get the guy down to $200!) respectively.
A typical Victory Model for Great Britain it bears German PD stampings. The town is in Saxony meaning it was carried by a Saxon pig.

Got this a couple months ago for $250 on GunBroker.
Another German PD (Wolfsburg) marking on this 1918 DWM P.08. My mother gave me a 1918 DWM Luger for my 21st birthday but it was stolen in 1985. I bought this as a replacement. I think I paid $375 for it.
Shipped to U.S. Customs in 1970 to supply federal officers from various agencies. I bought it in 1992 from a retired agent who said he carried it for 18 years. Paid $185. This is a daily carry piece for me. This makes 3 original LE guns in nickel I own.
Bought this about 4 years ago for $265 on Auction Arms. More than I wanted to pay but exactly what I was seeking and as the old saying goes, the time to buy is when you find what you want. This is the second of my daily work guns. Stamped for the Corpus Christi PD.
Used by the Atlanta PD (according to the dealer selling them about 6 years ago) this 659 is my most purely functional gun. I think it's ugly but does exactly what I need it to do. Lives in my PU truck. Paid $232 on Auction Arms.