President Obama said in December that the federal government has "bigger fish to fry" when asked if the feds would go after marijuana users. Some states have passed laws to legalize medical marijuana or allow people to have small amounts of the drug, contradicting federal law.

On Fox and Friends this morning, Steve Doocy asked Judge Andrew Napolitano whether President Obama has set a precedent as many states try to pass gun laws to

block stricter federal legislation. He explained that state authorities could legally choose not to enforce a federal gun law that goes against state law, but that the feds need the help of state and local authorities to enforce laws.

"Our home state of New Jersey could not, for example, use the police to frustrate federal law enforcement. What it could say to state and local police (is) 'you will not cooperate.' That will make federal enforcement of tighter federal gun laws nearly impossible," said Napolitano.

Watch the discussion:

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