It is disappointing that the Rhode Island Supreme Court, in a 3-1 ruling, has made it harder to prosecute legislators for ethics violations — though encouraging that the state’s new chief justice, Paul Suttell, wrote an impressively reasoned dissent.

The court ruled that legislators’ “core legislative functions” cannot be used against them in cases of official corruption. That seems something of a reach, for two reasons: the voters of Rhode Island amended the state constitution in 1986 to permit such prosecution; and the U.S. Supreme Court has addressed the issue of official misconduct at the federal level and come to a different conclusion.

Still, this is by no means a clear-cut, black-and-white issue. Legislators need to be able to vote on and pass legislation without being trapped into illegalities at every turn. Otherwise, no one will want to do the job — and if Rhode Island needs anything, it needs more good people, not beholden to special interests, willing to do that job.

The ruling centered on a case against former Senate President William Irons, who was accused of voting to benefit the pharmacy giant CVS while collecting hundreds of thousands of dollars in insurance commissions from Blue Cross on a health-insurance policy for CVS employees in Rhode Island.

Mr. Irons asserted that he cannot be taken to task under the venerable “speech in debate clause” of the constitution, which was devised for a very good reason: to protect lawmakers from being unjustly harassed by other branches of government and pernicious individuals for carrying out their legitimate duties.

On the other hand, it was never intended to be a blanket protection from ethics guidelines, as the U.S. Supreme Court has repeatedly asserted in rulings about a similar clause in the U.S. Constitution.

Mr. Suttell himself noted the case presented the judges with two parts of the constitution that seemed to clash. Yet he recognized, correctly, that Rhode Island amended the state’s constitution to permit the prosecution, under narrow circumstances involving the Ethics Commission, of all elected officials — including legislators. The majority of his colleagues, unfortunately, gave short shrift to that part of the constitution, while reading the speech-in-debate clause more broadly than their counterparts on the U.S. Supreme Court.

What to do now?

Governor Carcieri has called on the General Assembly to pass a resolution to place a constitutional amendment on the November 2010 ballot to strengthen the Ethics Commission, saying such a move is needed “to regain confidence and trust of the people of Rhode Island.”

That seems a good idea. Let the voters make it very clear whether they want their legislators, in their official conduct, bound by the ethics regulations that have governed them for more than two decades.