Legislation to increase Alaska’s state motor fuel tax rate for the first time since 1970 is in a calendar crunch. It was still in the House Finance Committee as of Tuesday, with lawmakers facing a May 19 adjournment deadline.

The measure would double the state tax of 8 cents to 16 cents a gallon, with the intent — but not a legally binding requirement — that the money go toward highway maintenance. The Alaska Constitution prohibits dedicated funds.

The tax hike is overdue, said the bill’s sponsor, Anchorage Rep. Andy Josephson, who noted the Parks Highway, the main route between Anc...