The Exxon Valdez disaster occurred nearly 20 years ago, but the case is still being sorted out in the courts.

The Supreme Court's reduction of punitive damages from $2.5 billion to $500 million may conclude the legal battle.

How much should be paid to victims who suffered losses from the worst oil spill in American history? When the supertanker struck a reef in 1989 and dumped 11 million gallons of oil into Prince William Sound in Alaska, 1,300 miles of Alaska coastline was fouled.

The accident killed hundreds of thousands of birds and marine animals. It disrupted the lives and businesses of people living in the region.

What was so disturbing about the case is that the accident was preventable. The ship's captain, Joseph J. Hazelwood, had been drinking heavily and left the bridge as a crew member was guiding the tanker through a difficult passage.

Exxon has paid $507 million in compensatory damages to more than 32,000 Native Alaskans, landowners and commercial fishermen. The Supreme Court ruled Wednesday that the company should not have to exceed that amount in punitive damages.

Justice David H. Souter wrote for the 5-3 majority that a 1-1 ratio between the two types of damages was appropriate in maritime cases.

Yet some may agree with Justice John Paul Stevens, who wrote in a dissent to uphold the $2.5 billion punitive damages set by the federal appeals court in California.

He said: "In light of Exxon's decision to permit a lapsed alcoholic to command a supertanker carrying tens of millions of gallons of crude oil through the treacherous waters of Prince William Sound, thereby endangering all of the individuals who depend upon the sound for their livelihoods, the jury could reasonably have given expression to its moral condemnation of Exxon's conduct in the form of this award."

The plaintiffs would have received $75,000 apiece; now they will receive $15,000.

It is not easy to determine what is fair and just compensation after such an event. The original punitive damages were $5 billion.

The case showed how extensive the environmental damage from such a spill can be. That it occurred due to carelessness, inattention and alcohol misuse was inexcusable.