Six years of inflammatory press coverage has irreparably biased potential jurors in a conspiracy and environmental crimes case against W.R. Grace & Co., according to court papers filed yesterday by the company's lawyers arguing that the trial should be moved out of state.

The Columbia-based chemical manufacturer is scheduled to go to trial in Missoula, Mont., on Sept. 11, 2006, on conspiracy, Clean Air Act violation and other criminal charges. The company and seven of its current and former executives stand accused of polluting a Montana mining town with deadly asbestos fibers and conspiring to cover up what happened there for nearly three decades.

The death rate in Libby, Mont., where Grace mined and processed asbestos-containing vermiculite, and surrounding areas is 40 to 80 times higher than elsewhere in the state and the nation, according to an indictment against Grace unsealed in February. A rare type of cancer that normally occurs in nine in a million individuals shows up in at least 20 of the approximately 8,000 residents of the area, government lawyers maintain.

Defense lawyers for Grace yesterday petitioned U.S. District Judge Donald W. Molloy to move the case, arguing that a jury pool in Boise, Idaho; Minneapolis; Denver; Salt Lake City; or Seattle would be free from the bias that they say infects Montana residents.

A June survey of 2,008 citizens eligible for jury service found that 55 percent had already decided that Grace is guilty, according to Donald Vinson, an expert hired by the defense team. Vinson reported that 90 percent of the respondents who believe Grace is guilty held their opinions with "great intensity," court papers said.

Since the Seattle Post-Intelligencer first published articles about Libby's widespread asbestos contamination in November 1999, potential jurors have been exposed to nearly 2,000 newspaper articles, two books and two documentary films, the lawyers said.

The 28-page defense brief cites letters to the editor in local newspapers that call Grace "a corporate serial murderer" for its conduct in Libby and for environmental pollution in Massachusetts chronicled in the book and movie "A Civil Action."

The company, which filed for bankruptcy protection in 2001 because it faced thousands of asbestos claims across the nation, has denied wrongdoing.

So have its current and former mine managers, vice presidents and other officials charged with taking part in the conspiracy. Grace employs 6,000 people worldwide, including 1,200 in Maryland. The company reaped profit of $140 million from sales of contaminated products between 1976 and 1990, the indictment said.

Montana U.S. Attorney William W. Mercer did not return calls yesterday. Prosecutors will have several weeks to respond to the defense motion.

Defendants face a high bar in seeking to transfer cases to friendlier venues, legal experts say. Next year's fraud and conspiracy trial of former Enron Corp. leaders Kenneth L. Lay and Jeffrey K. Skilling, for instance, will take place in Houston even though thousands of the city's residents lost jobs and pension savings when the energy trader collapsed in 2001.

An office of the Environmental Protection Agency is in downtown Libby, Mont., a sign of the town's asbestos problem.