The station tested three drivers under the influence under controlled conditions to see just how dangerous driving while stoned can be.

When Washington legalized pot in December, a blood-marijuana limit that makes it illegal to drive with 5 nanograms or more of THC per milliliter was established.

KIRO-TV decided to put the legal limit to the test, and arranged for three volunteers to get high and drive, and the report has gone national. The Seattle news station got three willing Washingtonians — a daily user, a weekend user and an occasional user — to smoke weed then get tested at the Cascade Driving School outside Olympia, while drug-recognition experts from the Thurston County Sheriff’s Office supervised.

The results? It seems driving stoned slows you down, yet also makes you dangerously inattentive, and that the more often you smoke, the more grass it takes to get you high.

Here's another story about driving while stoned from Fox News.