Which agency is primarily responsible for investigating interstate crimes and serial killings?

• A. IRS
• B. FBI
• C. DEA
• D. NTSB

Answer: (B)

Criminal cases that involve actions crossing state lines or affecting multiple jurisdictions require federal authority. The agency best suited for these interstate investigations is the Federal Bureau of Investigation. It has nationwide reach, the authority to coordinate multi-jurisdictional efforts, and specialized resources for violent crime and serial offenses. This means it can connect patterns across different states, share evidence, and lead investigations that local or state agencies alone cannot manage when crimes spill over borders or involve coordinated, cross-state activity. In contrast, the Internal Revenue Service handles tax crimes, the Drug Enforcement Administration focuses on illegal drugs, and the National Transportation Safety Board investigates transportation accidents, not serial killings or interstate criminal conspiracies.