SALEM, Ore. — Oregon’s Democratic Gov. Tina Kotek on Monday signed into law a bill that recriminalizes the possession of small amounts of drugs, ending a first-in-the-nation experiment with decriminalization that was hobbled by implementation issues.

The new law rolls back a 2020 voter-approved measure by making so-called personal use possession a misdemeanor punishable by up to six months in jail. It also establishes ways for treatment to be offered as an alternative to criminal penalties by encouraging law enforcement agencies to create deflection programs that would divert people to addiction and mental health services instead of the criminal justice system.