DENVER (AP) – A long-simmering marijuana driving debate in Colorado appears to be nearing an end. The state House gave unanimous approval Tuesday to a bill setting pot blood limits for drivers.

The proposal has sponsors from both parties who argued that it’s time Colorado finally set a pot driving standard. Colorado legalized marijuana last year along with Washington state. But unlike Washington, Colorado did not set a pot driving limit to go along with legalization.

“We have a problem. The problem is, we have people who are deciding to smoke marijuana and get behind the wheel,” said Rep. Rhonda Fields, D-Aurora.

The bill would say that drivers are too high if their blood contains more than 5 nanograms of THC per milliliter. THC is the psychoactive ingredient in marijuana.

Similar measures have failed three times before in the Colorado Legislature.

This year’s pot driving bill is slightly different because people accused of driving stoned would be able to argue that they were sober despite higher blood levels. Marijuana driving limits in Washington and other states are like drunken-driving laws, where drivers in excess of legal standards can’t claim they were sober.

Colorado’s marijuana driving bill has also been changed to state that police can’t use medical marijuana patient cards as evidence in a driving-high case. A medical-marijuana card also can’t be used as probable cause to test a driver’s blood for THC.

One of the marijuana driving sponsors, House Republican Leader Mark Waller, said the changes were “necessary to get this bill moving forward.”

Democratic Gov. John Hickenlooper supports the blood standard for marijuana.

One marijuana advocacy group said the bill still goes too far. The Colorado Springs Medical Cannabis Council argues that frequent pot users have elevated blood levels even when sober and could be ensnared in legal battles to prove they are able to drive.

The head of that group, Jason Warf, said bill opponents are hoping the bill will be defeated in the Senate, where similar bills have failed three times. Warf said the blood standard isn’t necessary because it’s already illegal to drive while impaired, with officer observation the primary evidence in most cases.

“We’ve had 100,000 people driving on cannabis now for over a decade,” said Warf, who doesn’t believe the driving-high problem has increased since legalization.

However, other marijuana industry advocates at the Capitol have dropped organized opposition to the pot DUI standard. Rep. Joseph Salazar, D-Thornton, argued that this year’s version won’t burden legal marijuana users.

“This is a good public safety bill and it takes into consideration the constitutional rights of individuals,” Salazar said.

By KRISTEN WYATT, Associated Press

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