MORGANTOWN, W.Va. (AP) -- Federal prosecutors will ask a judge this week to further delay a long-running lawsuit by investors who accuse Massey Energy of lying about its safety record to inflate stock prices before the Upper Big Branch mine disaster.
A previous order to delay the investors' case expired last week, and U.S. Attorney Booth Goodwin wants a new extension until July 15.
U.S. District Judge Irene Berger will hear the motion in her chambers Thursday afternoon in Beckley.
Goodwin, who asked that the hearing be held in private, said he needs to protect the integrity of evidence gathered in the continuing criminal probe of the 2010 disaster that killed 29 men. Berger will get an explanation that shows the risks to his case "are more than speculative or abstract," he wrote in a motion last week.
The defendants in the civil case either do not oppose or have taken no position on the delay request.
Some of the defendants in the civil action "may be or may become" targets of the criminal probe, Goodwin said. Among them are former chief executive officer Don Blankenship, his successor, Baxter Phillips, and former chief operating officer Chris Adkins.
"At present, these individual defendants have no access to the vast majority of the evidence material to the criminal investigation," Goodwin wrote. "They do not know, in other words, what information might be in the government's possession."
Sharing evidence now would reveal both the status and direction of the criminal investigation, Goodwin said.
At worst, he said, it could let the potential criminal targets "shape their own statements" to the investigation or obstruct justice by influencing the testimony of others.
Investors led by the Massachusetts Pension Reserves Investment contend that Massey repeatedly lied about its safety record, artificially inflating stock prices between 2008 and 2010. They say shareholders had no idea of the company's abysmal record and history of violations until after the southern West Virginia mine exploded.
Massey has since been bought out by Virginia-based Alpha Natural Resources Inc.
Four investigations found the blast at Upper Big Branch was sparked by worn and broken equipment, fueled by accumulations of methane gas and coal dust, and allowed to spread because of clogged and broken water sprayers.
Investigators also found "systematic, intentional and aggressive efforts" to hide problems and throw off inspectors, including the falsification of safety records.
Former superintendent Gary May and security chief Hughie Elbert Stover are behind bars for their actions at the mine.
A former president of another Massey subsidiary, meanwhile, is awaiting sentencing for conspiracy June 25 in Beckley.
David Craig Hughart, who is cooperating with federal prosecutors in the continuing criminal probe, has testified that advance warnings of inspections were a widespread company practice. When Berger asked at his plea hearing who created that policy, he implicated Blankenship.
The former CEO's attorneys, however, say Blankenship did nothing wrong.