Final answer:
Federal question jurisdiction comes into play when a case involves the Constitution, federal laws or treaties, or when the U.S. government is a party to the case. Any case that invokes the U.S. Constitution or federal law can potentially be heard in federal courts, regardless of whether it is a criminal or civil matter.
Step-by-step explanation:
Federal question jurisdiction comes into play when a case involves a 'federal question' such as the Constitution, federal laws or treaties, or when a 'federal party' is involved and the U.S. government is a party to the case. Any case that invokes the U.S. Constitution or federal law can potentially be heard in federal courts, regardless of whether it is a criminal or civil matter. For example, cases involving federal crimes like assault with a gun or civil violations of federal law like employment discrimination can be argued before the federal courts.