Maine’s opportunity to ensure the safety of its coastal waters was improved recently by the outcome of a case in the state of Washington. The ruling suggests Maine can keep its hand in the business of overseeing oil-tanker operations, while respecting the Coast Guard’s duties in this same area.

The case in Washington came about after state officials there asserted Washington’s right to monitor tankers coming into port. Washington devised its rules after the Exxon Valdez spill in 1989. The Coast Guard and the tanker trade association Intertanko disagreed, claiming the tankers fell under federal jurisdiction only. Two weeks ago, the 9th U.S. Circuit Court of Appeals upheld almost all of the state’s regulations that covered crew evaluations, spill-prevention plans, training and drug and alcohol testing.

Though the victory for Washington was not total — the court rejected regulations that required tankers to cover specific equipment — it was extremely encouraging for Maine. This state, too, has had lengthy discussions with the Coast Guard and Intertanko over the Department of Environmental Protection’s role in monitoring tankers and the possibility of being similarly taken to court has influenced decision-making here.

There are several differences between the Washington and Maine laws. Maine, for instance, has 25 years’ experience with state laws that have allowed it to work with the Coast Guard in monitoring tankers and it has used its authority sparingly and judiciously. The current flap is over Maine’s decision to update its statutes to reflect federal regulations. Done properly this should not be a problem for anyone.

The Coast Guard has some good reasons to have reservations about states regulating tankers. International trade agreements, under which the tankers often operate, properly are made at the federal level. And the Coast Guard believes it has sufficient authority to oversee and control potential pollution problems brought about by the tankers, and so sees state interference as both redundant and a nuisance.

It doesn’t have to be, as Maine’s track record makes clear. Instead, state participation could add local expertise and a backup system under unusually egregious situations.

Now that the outcome of the Washington suit strongly suggests that Maine has been well within its rights, it gains footing in its discussions with the Coast Guard. If it uses this leverage carefully, it is likely to find agreement with its federal partners where before it found merely debate.