OLYMPIA, Wash. (AP) — The Washington state Supreme Court has ruled people can be cited for driving under the influence for driving while high.

The decision upholds the state’s decade-old law regulating marijuana use behind the wheel of a car.

The Seattle Times reports all nine justices on Thursday rejected Douglas Fraser’s argument that his 2017 DUI was based on an arbitrary and vague standard for THC levels in the blood.

Although the justices acknowledged that the correlation between THC levels and impairment is challenging to pinpoint, they found that blood measurements nevertheless provide a useful and constitutionally acceptable measurement.