Los Angeles police today warned people who use now-legal recreational marijuana to designate others to drive in light of figures showing an increase in DUI-drug arrests following the drug’s legalization.

Recreational marijuana use became legal January 1, 2018. DUI-drug arrests increased 32 percent in the city of Los Angeles during the first six months after the effective date, the Los Angeles Police Department said in a statement.

Marijuana, like any impairing substance, negatively affects skills required for safe driving,” the LAPD said.  Effects include slowed coordination and reaction time, distorted perception and attention, diminished ability to track many moving parts at once and increased reaction time and lane deviation.

While there is not a breath test to aid officers in determining whether a motorist is impaired by marijuana use, they can arrest people who appear to be impaired and have them evaluated by a Drug Recognition Expert, police said.