How many federal police agencies can you name?
The list is getting longer. CIA, FBI, NSA, ATF, DEA, INS, TSA, Secret Service, Customs, Border Patrol, U.S. Marshals Service, to name a few. But there are many more. IRS agents are armed. So are EPA agents. Agents with the Bureau of Land Management are not only armed, they have a SWAT team. Now agents with the Office of the Inspector General are getting into the police business, as Ryan Scott found out when his dog was shot and killed by an unnamed investigator.
Expect more stories like this. The number of federal criminal laws has been steadily expanding (pdf). To enforce those laws, Congress hires more agents. The agents, in turn, conduct more raids. To process the cases, Congress hires more prosecutors. And then, of course, Congress builds more prisons.