New Jersey voters approved a measure legalizing recreational marijuana that goes into effect on Jan. 1. But state legislators still have not passed the bills necessary to set up the legal marijuana market.

“It’s going to happen before Jan. 1. But, hypothetically, it could be chaos,” says marijuana advocate Scott Rudder.

Without passage of a law, it could be legal to smoke weed by 2021 but illegal to buy it.

"It really is incumbent on the Legislature to come up with this compromise so we don't have a constitutional dilemma,” Rudder says.

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Rudder is the head of the New Jersey Cannabusiness Association and is also a former Republican state assemblyman.

"At the end of the day, it is frustrating. But this is part of the process. There's nothing surprising going on right now,” Rudder says. “I do think that some of the legislators thought this was going to be easier because there was so much debate, so much discussion, over the last couple of years."

Committees in the state Assembly and Senate passed two different versions of the bill last week. Final votes are held up while each side negotiates over the differences. Any bill would still need to be signed by Gov. Phil Murphy.

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“It’s a big bill. We’re not just – we’re accomplishing a whole lot of things, right?” says state Assembly Speaker Craig Coughlin. “We’re accomplishing a great deal of social justice. We’re also starting a new industry.”

Issues that the lawmakers are debating include how big of a tax to put on legal cannabis and whether to limit the number of sellers and growers.

“If this were easy, it would have been done a long time ago,” says Rudder. “People have very specific concerns about this whole process.”

A bill that would decriminalize marijuana possession passed in the state Senate last week but stalled in the state Assembly.