A federal judge in Oklahoma ruled that a law preventing marijuana users from owning guns is unconstitutional.

This comes after officers arrested a man and said they smelled marijuana in his vehicle, then later found a gun.

Gun stores like Advanced Combat in Tulsa sell guns by the thousands every year.

From the moment a customer walks through the door, the staff are making an important decision, asking themselves if they are comfortable selling the customer a gun.

Manager Mark Heffron said that includes the customer’s behavior, speech, and even the way they smell.

“You can smell alcohol or you can smell marijuana. We’ve had guys come in here and fumigate the whole shop. The smell is an obvious smell. We just have the right to tell them, 'no,'” Heffron said.

Heffron said the ATF provides dealers guidelines and requires them to make these judgement calls.

“I always just tell them honestly. The best policy is just to be straight up and to tell you, ‘hey, I just don’t want to sell a gun to you today. You smell like weed. Sorry,'” Heffron said.

To go a step further, Wester District of Oklahoma Judge Patrick Wyrick said people who are considered a danger should not be sold a gun.

Court documents show this wasn’t the case when Jared Harrison was arrested during a traffic stop on his way to work at a medical dispensary in Lawton last May.

Officers said they smelled marijuana in the car, searched it, and found a gun.

Wyrick said the mere use of marijuana and possession of a firearm is not a constitutionally permissible means of disarming Harrison and dismissed the case.

OK2A founder Don Spencer said this is a win for the 2nd Amendment, but said it never should have come to this.

"No person should be disbarred their firearm or their rights until due process of the 5th amendment takes place. Period. That's what makes this even more interesting and impactful from this court ruling,” Spencer said.

Spencer said when cases like Harrison's go to court, the violation of rights has already taken place and it's only a win for the 2nd Amendment if an arrest never happens.

"We don't look at it as rights going forward. We look at it as rights being restored that never should have been taken away to begin with,” Spencer said.