I know the list of federal agencies under the "Tips" tab is extensive, so here are some quick descriptions for the major law enforcement agencies to help get you started. Thank you for the suggestion, Ashley!
Federal Law Enforcement Agencies
Department of Homeland Security
Federal Emergency Management FEMA is responsible for leading the effort to prepare the nation for all hazards and effectively manage Federal response and recovery efforts following any national incident. FEMA also initiates proactive mitigation activities, trains first responders, and manages the National Flood Insurance Program.
US Coast Guard Protects the public, the environment, and U.S. economic interests in the nation’s ports and waterways, along the coast, on international waters, or in any maritime region, as required, to support national security.
Customs and Border Protection CBP is responsible for protecting our nation’s borders in order to prevent terrorists and terrorist weapons from entering the United States, while facilitating the flow of legitimate trade and travel.
Immigration and Customs Enforcement ICE is the larges investigative arm of DHS. It is responsible for identifying and shutting down vulnerabilities in the nation’s border and for economic, transportation and infrastructure security.
Federal Law Enforcement Training Center FLETC provides basic and advanced training to law enforcement professionals from 81 Federal agencies, plus state, local and international law enforcement agencies, to help them fulfill their responsibilities safely and proficiently.
United State Secret Service USSS protects the President and other high-level officials and investigates counterfeiting and other financial crimes, including financial institution fraud, identity theft, and computer fraud; and computer-based attacks on our nation’s financial, banking, and telecommunications infrastructure.
Transportation Security Administration TSA protects the nation’s transportation systems to ensure freedom of movement for people and commerce.
United States Marshals Service The Marshals provide support and protection for the Federal courts; apprehending the majority of Federal fugitives; operating the Witness Security Program; maintaining custody of and transporting Federal prisoners; they also manage and sell seized property.
Drug Enforcement Administration DEA is the lead federal agency for enforcing narcotics and controlled substances laws and regulations.
Bureau of Alcohol, Tobacco, Firearms and Explosives ATF enforces the federal firearm laws, primarily involving firearm, arson and explosive violations. ATF also investigates alcohol and tobacco tax diversion crimes. ATF is responsible for regulating the industries of firearms and explosives.
Bureau of Prisons BOP operates the federal prisons in a safe, humane and cost-efficient manner.
Federal Bureau of Investigation The FBI is charged with investigating all violations of Federal law, except those that have been assigned to another Federal agency. FBI conducts civil and criminal investigations, including counterterrorism, cyber-crimes, organized crime and financial crime.