It was a glorious four-day holiday weekend, blessedly and astonishingly free of major incident. Then tragedy struck a day later in the familiar form of a head-on crash involving a moped.

Everything about Wednesday’s accident had the inevitability of a game of Russian roulette. Two day trippers riding tandem on a rented vehicle ran headlong into a Vineyard Transit Authority bus on Eastville avenue in Oak Bluffs near the hospital, the site of fatal moped accidents in 1989 and 2006. One of this week’s victims was airlifted to Boston with serious injuries; the other was treated at the Martha’s Vineyard Hospital. Thankfully, they are both expected to recover.

The arguments against moped rentals have been made repeatedly here and elsewhere and seem inadequate to the sense of outrage at another predictable calamity. Whether the riders themselves really understood the risks of their joyride, the first responders who have to deal with the devastating consequences of moped accidents certainly would have — but they are not figured in that calculation.

What is left to say but this: Enough, already.

There is overwhelming public support to ban mopeds on Martha’s Vineyard. Only two towns still license rentals: Tisbury and Oak Bluffs, and Oak Bluffs tried in vain this spring to outlaw them, only to be thwarted by order of a superior court judge, who found that a ban on rental mopeds would violate state law.

But there remains one legal way to do it: a home rule petition to the Massachusetts legislature.

The process, outlined to the Oak Bluffs selectmen in April by town counsel Ronald H. Rappaport, will take some time, but is simple enough.

At a regular or special town meeting, the voters must agree to petition the state legislature to pass special legislation exempting that town from state law for a limited purpose under a legal provision called home rule.

Typically, after the legislation is passed the town must vote again to accept it. The process has been used in several Vineyard towns to authorize the sale of liquor.

Citizens of Martha’s Vineyard who care about the safety of our roads and respect the police, fire and emergency medical personnel who perform the thankless task of tending to the casualties should insist that Tisbury and Oak Bluffs selectmen start these steps now to ban rental mopeds once and for all.