Supreme Court Justice Antonin Scalia said today it's possible that new gun restrictions could be upheld by the high court, but it's hard to say which specific ones.

"It will have to be decided in future cases," Scalia said on Fox News Sunday.

It's also hard to say whether Congress will pass any new gun control measures.

Democrats have proposed new rules in light of the Colorado theater shootings, but leaders of the Republican-run House have vowed to block them; there's also some question as to how hard President Obama might push for new gun laws.

As for the constitutionality of new legislation, Scalia noted that the United States had weapons laws at the time the Founding Fathers wrote and ratified the U.S. Constitution, including the Second Amendment right to bear arms.

He cited one law that banned "a really horrible weapon just to scare people, like a head ax or something."

Scalia also said: