ANCHORAGE -- A federal judge has ordered Exxon Corp. to stand trial in April for the Exxon Valdez oil spill after refusing the company's request to dismiss a five-count criminal indictment stemming from the tanker's wreck in March 1989.

The ship, skippered by Joseph Hazelwood, was sailing through icy waters of Prince William Sound when it struck a charted reef and dumped about 11 million gallons of crude into Alaska waters.

Thousands of birds and marine mammals died, commercial fishing seasons were disrupted and miles

of shoreline were oiled. It was

the worst tanker spill in U.S. history.

At Friday's hearing, defense lawyers said federal pollution laws weren't intended to be used to prosecute shipowners for the acts of a vessel's captain and crew.

Exxon lawyer Patrick Lynch also argued that because the tanker was owned and operated by Exxon Shipping, it was wrong to name the parent company in the indictment along with the subsidiary.

Both Exxon Corp. and the shipping subsidiary are charged with criminal violations of the federal Clean Water Act, the Refuse Act, the Migratory Bird Treaty Act, the Ports and Waterways Act and the Dangerous Cargo Act.

Lynch said Exxon Shipping is a separate company controlled by an independent board of directors.

But federal prosecutors say Exxon dominates its subsidiary and makes all the important decisions for Exxon Shipping, which the government called "a corporate puppet on a carefully calibrated string."

U.S. District Judge H. Russel Holland denied the motions to dismiss as well as a series of other technical arguments by the companies, including Exxon Shipping's claims that crude oil is not a pollutant under the Clean Water Act.

Hazelwood was acquitted in Anchorage Superior Court of charges of operating a vessel while under the influence of alcohol and felony criminal mischief. He has appealed his misdemeanor conviction of negligent discharge of oil.