I’ll give the U.S. Marshals and the Secret Service a pass because of seniority.
Now I do understand that because the federal government doesn’t have a general police power authority, federal law enforcement agencies have to be authorized by the bills enacting the federal laws they cover. But I don’t see what those agencies do that couldn’t/shouldn’t be handled by the FBI.
The FBI is a law enforcement agency, the BATF is primarily a regulatory agency. DEA though, nit sure what they do that couldn’t be handled by the FBI.
I think that the answer is historical. (Of course neither of them are actually independent agencies, they are components of the Department of Justice).
Both ATF and DEA descend from offices that were originally part of Treasury. ATF started as part of the Office of Internal Revenue, wound up as the Bureau of Prohibition, and was transferred to DOJ in 1972 (after assuming responsibility for both Firearms in 1934 and Explosives in 1970).
DEA comes from the 1968 merger of Treasury’s Bureau of Narcotics and FDA’s Bureau of Drug Abuse Control into DOJ’s Bureau of Narcotics and Dangerous Drugs which merged with various other federal operations (including customs) in 1973 to create DEA.
Both agencies also have significant regulatory functions in addition to their law enforcement activities, while I don’t think that FBI has anything similar.
Okay, so although their modern incarnations only date from the 1970s, they inherited their operations from older institutions that go at least as far back as the FBI. Got it.
Historically there has been a lot of opposition to the concept of a federal police force, so several specialized federal law enforcement agencies were developed instead. Logically there is much to be said for the creation of such a federal police force as a great many criminals commit crimes subject to enforcement by multiple agencies–for example the classic motorcycle gang involved in gun running, illegal drug sales, and bank robberies–and of course interstate flight to avoid prosecution.
OP, how are you defining “independent”? In one sense, all government agencies are independent, and in another sense, none of them are.
Mainly in the sense of “not a department of the FBI”, as I mentioned.