The effort to protect marine mammals from the damaging effects of underwater sonar testing begs for a compromise between the U.S. Navy and environmental groups.

Both sides represent issues of critical importance - environmental protection and military readiness - and both sides make compelling arguments in their favor.

But in the absence of general agreements on best practices, those arguments too often get played out in federal court, leaving fundamental issues unsettled and both sides ready to litigate another day.

The latest example was a ruling issued Monday by Judge Florence-Marie Cooper. She rejected the Bush administration's attempt to exempt the Navy from special restrictions on the use of mid-frequency active sonar in exercises off the coast of Southern California.

The judge cited the Navy's own studies, which showed that the sonar's decibel levels can cause permanent injury, or death, to marine mammals.

Her restrictions were issued after the Navy and the plaintiffs failed to reach a compromise, leaving it in her hands.

This wasn't the first time Cooper ruled against the Navy and its use of mid-frequency active sonar. In 2006, the judge briefly halted sonar use during Hawai'i's Rimpac exercises. It took a late compromise by the Navy and a coalition of environmental groups to reach an agreement that allowed limited sonar use during the vital military exercise.

But the issue will not go away. As preparations continue from Rimpac 2008, the Navy has released a draft environmental impact statement it hopes will support a blanket authorization for sonar training in the Pacific, eliminating case-by-case legal battles.

In the interests of our military readiness, it's a worthy goal. But it won't be reached without cooperation from the environmentalists. Let's hope they can settle out of court.