Final answer:
Offenses near the boundaries of a county or city can be prosecuted within that jurisdiction, with law enforcement officers from the area having the authority to act in these cases. The complexity of the U.S. jurisdictional system allows some cases to be heard in both state and federal courts, especially when federal laws or constitutional issues are involved.
Step-by-step explanation:
In the United States, offenses committed within a certain proximity to the territorial boundary of a county or city may be prosecuted within that jurisdiction. Law enforcement officers from either jurisdiction, be it county or city, can exercise authority in these boundary zones. This means that a county police officer can respond to emergency calls, patrol specific areas, and work at local jails, while federal officers, such as those from the FBI or ATF, concentrate on federal matters. As such, a local law enforcement officer has the authority to make arrests and conduct investigations within their jurisdiction, which can overlap with adjacent jurisdictions under certain circumstances.
When a crime involves a federal law or the U.S. Constitution, the case may be heard in both state and federal courts, with the possibility of cases moving up to the federal level after exhausting state appeals. This dual court system showcases the complexity of jurisdiction within the United States, where different types of officers and courts handle various violations, from local to federal offenses.