Recreational marijuana becomes legal in the state two weeks from today.

That, of course, is because California voters approved Prop 64 last year.

But more than just legalizing weed for people age 21 and up, the law gives people with a criminal cannabis history a chance at a clean - or cleaner - slate.

Advocates say that part is under-used.

When California voters went to the polls in Nov. 2016, they turned what was once illegal into something legal. Possessing an ounce of weed was an infraction with a fine; now, for adults over 21, it's legal, according to state government.

But even more serious offenses were reduced. Selling an ounce used to be a felony; It's simply a misdemeanor now.

Prop 64 allows people convicted under the old law to have their sentences and convictions reduced to what they'd be under current law. And there's no time limit. Some attorneys tell ABC10 News they're handling cases from as far back as the mid-90s.

"We see it as a lesser crime, so we don't want the harsh penalty of a felony on their record," Sacramento attorney Mark Reichel told ABC10 News Monday.

Reduced charges can help communities most impacted by marijuana arrests, he said.

"There definitely, definitely was a disproportionate effect on those in lower socio-economic areas and so forth and people of color," Reichel said. "They were clearly more targeted and likely to get cited for these, and these convictions will stay on their records and obviously have disabling effects on them, so this really is equitable. That's the whole concept behind it."

But advocates say, this Prop 64 provision is under-used.

The Drug Policy Alliance estimates that statewide, there about a million people eligible for conviction reductions or even clean slates.

But numbers from the Judicial Council of California show, between Nov. 2016 when the law was approved and Sept. 2017, only about 5,000 people had petitioned for a reduced marijuana charge.

"It is very under-utilized," Reichel said. "It wasn't very well publicized. I think the more, the headlines were made that marijuana will now be legal, recreationally."

People convicted of any of these four specific charges are eligible for reclassification: Possession of Marijuana (Health and Safety Code § 11357), "Growing" / Cultivation of Marijuana (H&S Code § 11358), Possession with Intent to Sell Marijuana (H&S Code § 11359) and Sales of Transport of Marijuana (H&S Code § 11360).

Rob Gold, Sacramento County Assistant Chief Deputy District Attorney, said that list of eligible charges "may be expanded. You're going to have to stay tuned what the court decides."

He said the Sacramento District Attorney's office has reviewed 247 petitions so far - most of which were for crimes that were previously felonies but under current law are lesser charges - and approved the vast majority of them.

"Of the 247, I'd say probably about 237 have been granted," Gold estimated.

It's a matter of filling out a petition and submitting it to the court where the person was charged. Once the district attorney's office approves the petition, it goes before a judge for final approval.

"It's not as complicated as a lot of people may think," Gold said. "It's a one-page petition and it can usually be processed within a month."

Advocates encourage people to contact their public defender's office with questions.

Eunisses Hernandez, LA-based policy coordinator with the Drug Policy Alliance, said the process is free.

The Drug Policy Alliance offers tips HERE.

Hernandez believes local governments need to do a better job publicizing this path to sentence/conviction reduction.

"We're going to see legal sales in January and yet there are people carrying these sentences from 5, 10 years ago," she said. "Now that constituents are able to change their offenses, local jurisdictions (need to help) repair the damage done by marijuana prohibition."

Having a cannabis conviction on someone's record can hurt everything from rental and employment applications to school loans the ability to vote.

"People shouldn't be afraid that if they have a serious conviction," Hernandez said, adding that most people with marijuana convictions are eligible for reduced charges, even people still serving jail or prison time or who are on parole or probation. A charge reduction could mean they're allowed to walk out of jail, having already served the time for the reduced sentence.

The Voluntary Legal Services Program of Northern California holds a Criminal Records Expungement clinic. According to the Drug Policy Alliance, these clinics "are hosted three times a week (Tuesdays, Wednesdays, and Thursdays) at the Asian Resources Sacramento Training Center (5709 Stockton Blvd, Sacramento, CA 95824) between 10:00 am and 4:00 pm."

Out-of-state convictions are not covered under this law.