(Newser) – The Supreme Court on Thursday ruled against Puerto Rico in a politically charged dispute over the island's power to enforce its own criminal laws. The justices ruled 6-2 that the US territory can't prosecute people for local crimes if they've already been convicted of similar charges in US federal court, reports the AP. The ruling helps clarify the island's legal status at a time when the issue has caused deep divisions between officials from the US and Puerto Rico. The court sided with two men who said the principle of double jeopardy prevented Puerto Rico officials from prosecuting them on weapons charges after they had already pleaded guilty to federal charges for the same offense. Puerto Rico officials had argued that the island could still bring charges under its own laws—something that the 50 states have power to do under the principle of state sovereignty.

But "there is no getting away from the past," wrote Justice Elena Kagan. "Because the ultimate source of Puerto Rico's prosecutorial power is the federal government ... the Commonwealth and the United States are not separate sovereigns." USA Today sums up the ruling thusly: "Puerto Rico has its own Constitution and elects its own leaders, but it remains under the thumb of Congress." Justice Stephen Breyer dissented from the majority decision, saying that over time, the source of Puerto Rico's criminal law "ceased to be the US Congress and became Puerto Rico itself, its people and its constitution." He was joined by Justice Sonia Sotomayor. (Read more Puerto Rico stories.)

