Massachusetts House Speaker Sal DiMasi was first elected to the legislature in 1978. For years he was a back-bencher whose influence slowly rose to the point that he was, in effect, a political fixer for his immediate predecessors, Speakers Charles Flaherty and Thomas Finneran. They were both bright and flamboyant men, but ethically challenged. Working behind the scenes, Mr. DiMasi was all but unknown to the public, and far from flamboyant. Few expected much of him as speaker.

But in 2007, when the untested Deval Patrick and Therese Murray succeeded Mitt Romney as governor and Robert Travaglini as Senate president, respectively, Mr. DiMasi emerged as the most influential of the “Big Three” in state government. He simply said no to Mr. Patrick’s more unrealistic and/or economically unsound proposals. This year, he routed the governor when Mr. Patrick made casino gambling the centerpiece of his legislative agenda.

That was just a couple of months ago, but since then Mr. DiMasi’s world has looked to be falling apart. In the last two months the state Republican Party has filed four separate ethics complaints against him –– the most recent being that he killed legislation that would have blocked a Fall River liquefied-natural-gas facility as a favor to his friend Jay Cashman, who then made $14.2 million selling the land for the proposed facility.

Other complaints were that Mr. DiMasi allegedly let himself be influenced by an unregistered lobbyist on behalf of ticket brokers (generally known as “scalpers”); that he improperly directed a contract to a Canadian software company; and that he accepted a free golf game from a casino developer.

The hint of Mr. DiMasi’s blood in the water has attracted two sharks who want to be the next speaker: Representatives Robert DeLeo (D.-Winthrop) and John Rogers (D.-Norwood). Earlier in the year, Mr. DiMasi had told this pair that he would remove them from the leadership if they persisted in campaigning for the speakership. It worked at the time, but no longer. During the recent budget debate, the supporters of both men were very actively soliciting votes.

No one we know on Beacon Hill is willing to predict how this will play out. Our guess is that if any of the ethics allegations results in formal charges, Mr. DiMasi is gone. But if they do not, a man with 30 years in the House will presumably not want to be run out of the building precipitously. In this scenario, he would serve at least until the end of the current term, which ends the first week of next January.

But the controversy has already had a bad effect on the functioning of the House. Minority Leader Brad Jones (R.-North Reading) may have put it best when he described the House in recent weeks as like the scene of a traffic accident on a major highway. All the traffic slows down. In this case the traffic is the business of the House and therefore of the whole state.