I am not a Law Enforcement firearm collector. I am simply an accumulator of various firearms when I see what I consider a good deal.
The following is a list of LE trade-ins I have accumulated:
SHOTGUNS:
MOSSBERG MODEL 500 ATP SHOTGUN - ALABAMA STATE HIGHWAY PATROL
REMINGTON MODEL 870 SHOTGUN - TALLASSEE, AL POLICE DEPARTMENT
REMINGTON MODEL 870TB SHOTGUN - RULEVILLE, MS
PISTOLS:
SIG SAUER MODEL P220 ST .45 ACP - SCOTTSBORO, AL POLICE DEPARTMENT
SIG SAUER MODEL P226 9mm - PELHAM, AL POLICE DEPARTMENT
SIG SAUER MODEL P226 .40 S&W - AUBURN, AL POLICE DEPARTMENT
SIG SAUER MODEL P229 .40 S&W - OPELIKA, AL POLICE DEPARTMENT
BERETTA MODEL 96 .40 S&W - RULEVILLE, MISSISSIPPI POLICE DEPARTMENT
REVOLVERS:
SMITH & WESSON MODEL 686 .357 MAGNUM - MEMPHIS, TN POLICE DEPARTMENT
SMITH & WESSON MODEL 10 (NO DASH) .38 SPECIAL - MONTGOMERY, AL POLICE DEPARTMENT
SMITH & WESSON MODEL 10-5 .38 SPECIAL - QUINNETT, GA POLICE DEPARTMENT
SMITH & WESSON MODEL 10-5 FACTORY NICKEL .38 SPECIAL - QUINNETT, GA POLICE DEPARTMENT
SMITH & WESSON MODE 10-6 .38 SPECIAL - MOBILE, AL POLICE DEPARTMENT SWAT
The only one of the above marked as a law enforcement firearm is the Model 10 no dash. The rest were obtained from a law enforcement distributor, and I have a record of where they came from in my purchase documents. It is possible some of these were not actually LE guns but acquired in confiscations or other means and traded-in.
The "Standard Catalog of Smith & Wesson" by Surpica and Nahaus does show pictures and information on various former marked S&W LE firearms. It could be a starter to attempt in making a collection list.