Another bill that would make marijuana legal for adults in Vermont was approved by the state Senate on Wednesday, the first day of a two-day veto session. H. 511 reflects a compromise between legislative leaders and Gov. Phil Scott, who vetoed a similar bill, S. 22, in late May.

It will now go the House, where it is unclear if a substantial number of House Republicans will agree to waive rules and allow its consideration during the veto session.

A three-quarters vote of the House will be required for the bill to be taken up on Thursday. If the House does not pass the bill during the veto session, H. 511 could receive a vote when the House next convenes.

The legalization language was added as an amendment to H. 511, a bill dealing with highway safety that had already passed the House. It would eliminate Vermont’s civil penalty for adults possessing one ounce or less of marijuana beginning in July 2018 and remove penalties for possession of up to two mature marijuana plants and up to four immature plants.

It would also create a study commission to develop legislation to regulate and tax marijuana for adult use. The amended bill would extend the time allotted by S. 22 for the commission to submit its report. It would also add additional agency directors and the defender general to the commission, and increase penalties for dispensing marijuana to minors or exposing them to cannabis smoke in cars.

One thing bill does not contain is the “impairment testing mechanism” requested by Gov. Scott, who wants a way to detect stoned driving, reports Aaron Smith at CNN Money.

There are no proven marijuana breathalyzers on the market, although two startups are working on it.

Gov. Scott, when he vetoed the first version of the legalization bill, claimed he isn’t “philosophically opposed” to legalization, but rather that he wanted to ensure certain public safety measures were in place.

“Vermont is poised to make history by becoming the first state in which the legislature and governor end the disastrous policy of marijuana prohibition,” said Matt Simon, New England political director for the Marijuana Policy Project. “Just over a year from now, adults will have the same freedoms to grow and possess cannabis that our neighbors in Maine and Massachusetts enjoy.

“The question is no longer ‘if’ Vermont will stop penalizing adult cannabis consumers, but ‘when’,” Simon said.

“There is no good reason for the House to delay passage of this modest and sensible legislation,” Simon said. “Now that Gov. Scott has agreed with the House and Senate that marijuana should be legal for adult use, House Republicans should follow the governor’s lead and vote to advance this compromise. Failing to waive the rules will only mean the marijuana regulatory commission has less time to do its important work.”

The Green Mountain State’s model of cannabis legalization is different from every other state that has legalized, in that its legalization bill does not allow for a legal retail market. It only legalizes personal use, possession of up to an ounce (which is an absurdly low amount, of course), and growing up to six plants at home.

The state has four legal marijuana dispensaries, but they are for medically authorized patients only. Vermont recently expanded its medical marijuana program to cover Parkinson’s disease, Crohn’s disease and post-traumatic stress order.

If Gov. Scott signed S. 511 into law, Vermont would be breaking new ground. Every other state with legal cannabis has done it through voter initiative rather than through the Legislature.

Legalization through a state legislature would be great news, giving more hope to the folks who live in states with no ballot initiate process in place.

Even if the bill becomes law, legalization won’t become official until July 2018. The Vermont Legislature convenes again in January, so it could still meet that target.

Fifty-seven percent of Vermont voters support allowing adults 21 and older to possess and grow limited amounts of marijuana, according to a statewide survey of 755 registered voters conducted in March by Public Policy Polling. Only 39 percent are opposed.