The Federal Bureau of Prisons is the Federal prison system. They have also subsumed the District of Columbia Prison System. The BOP issued the Ruger P89/P95s but has transitioned the last few years to the Beretta Vertec 9mms in DOA guise. A step up in my opinion. The Bop also uses AR15s, 9mm Colt Carbines, Remington 870 shotguns, and a very wide assortment of less lethal weapons and munitions. There are also a few Remington 700 sniper rifles in use around the Bureau.
The Bureau of Immigrations and Customs Enforcement, especially the Border Patrol has historically had a very high rate of use of its issue firarms, not just on the border but when they are involved in high risk search warrants and arrests of violent illegal aliens. Don't put them down if you haven't done your homework.