AUGUSTA — An effort to establish a blood level limit to determine whether a driver is impaired from marijuana use may have to wait at least another year, following an unexpected vote Friday in the House of Representatives.

The House voted unanimously and without debate to reject a bill that would set a blood level limit allowing police to charge impaired drivers with operating under the influence.

The Senate previously approved the bill, after a debate pitting those who believe that setting a blood level limit is a public safety issue against those who argued there is not yet a scientific consensus on impairment based on blood levels of THC, the psychoactive compound in marijuana.

The House’s decision to reject the limit effectively stalled the proposal – at least for one year.

Rep. Lori Fowle, D-Vassalboro, House chairwoman of the Criminal Justice and Public Safety Committee, said the disagreement between the House and the Senate means that the proposal is dead for the current session. While bills with that status have been revived in the past, Fowle said she didn’t expect that outcome this year because the legislative session is drawing to a close.

A majority of the Criminal Justice and Public Safety Committee voted against the bill March 10.

According to the National Conference of State Legislatures, 17 states have laws setting limits on THC in the bloodstream of someone operating a vehicle.

Several of those states have set the amount between 1 and 5 nanograms per milliliter. The Maine bill sought to impose a 5 nanogram limit – the same as in Colorado and Washington state, where recreational marijuana use is legal.

A bid to legalize recreational use in Maine could appear before voters in November, pending a decision by a Superior Court judge on whether supporters submitted enough valid signatures to qualify for a ballot question.

A number of laboratory studies have determined that marijuana degrades one’s driving ability. However, research on whether it plays a role in accidents has been mixed.

Police already test for alcohol after fatal crashes and request testing for the presence of drugs.

Steve Mistler can be contacted at 620-7016 or at:

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