Becuase the federal government is highly compartmentalized, and in most cases, you won't see inter-agency co-operation. Think about it. FBI. Federal Bureau of Investigation. Yet, just about every other federal agency has it's own investigative and enforcement bureau. DEA. BATFE. ICE. Secret Service. Dept. of Agriculture (foor stamp fraud, if I recall correctly). You name the agency, they prbably have an investigative and enforcement department in-house. Good news for anyone interested in a career in federal law enforcement (plenty of jobs), but in many cases it seems to be a waste of tax dollars to replicate services for each agency.