Your guide to Proposition 36: Stiffer penalties for some drug and theft crimes

This measure asks voters to change parts of Proposition 47, a controversial ballot initiative passed in 2014 that turned some nonviolent felonies into misdemeanors.

Proposition 36 would change the law to make a third offense of theft, regardless of the value of the merchandise, a felony punishable by up to three years in prison. The measure also would make possession of fentanyl a felony. Finally, the measure would impose a “treatment-mandated felony” the third time someone is arrested for drug possession.

Proponents include prosecutors and law enforcement leaders, including the California District Attorneys Assn., which is mostly comprised of conservative prosecutors, and the California Sheriff’s Assn. Noteworthy politicians who support Proposition 36 include San José Mayor Matt Mahan and San Francisco Mayor London Breed. The California Republican Party has endorsed the measure.

Large retailers, such as Walmart, Target and Home Depot have been major contributors to Proposition 36.

Supporters argue that tougher criminal penalties are needed to curb theft and the rising use of fentanyl.

Gov. Gavin Newsom and top Democratic legislative leaders initially opposed asking California voters to alter Proposition 47, but then proposed their own ballot measure as an alternative to the prosecutor-led, tough-on-crime measure. They quickly withdrew that proposal, however, just days after announcing it.

Criminal justice reform groups and human rights activists have been outspoken against altering Proposition 47, saying that it will lead to an increase in the state’s prison population and the associated costs. California Attorneys for Criminal Justice, which is composed of criminal defense attorneys, has called it “draconian.”