Jonathan Snare, the department's acting solicitor, told Miller that a House Committee on Education and Labor probe of last month's disaster could jeopardize the federal Mine Safety and Health Administration's investigation and the agency's ability to "enforce the law and hold violators accountable."

But Miller, the California Democrat who chairs the committee, said no.

"It is the committee's responsibility and obligation to conduct an independent investigation of this tragedy," responded Miller. "The families of the miners who died and active miners all over the country deserve an objective and independent review of the tragedy that will help us to prevent future tragedies."

Miller's committee has scheduled an Oct. 3 public hearing on the disaster. Committee staff members will begin witness interviews today, starting at MSHA's district office in Denver with three officials involved in approving the mine's roof-control plan.

That plan would have addressed the pressures that bore down on the mine's walls before they gave way in a catastrophic implosion Aug. 6, trapping and killing six miners excavating pillars of coal used to support the mountain overhead. Three rescuers died in a second implosion 10 days later.

By interviewing witnesses before MSHA's law-enforcement team can, Snare argued, "your parallel investigation could prejudice the testimony of other witnesses, subject witnesses to possible intimidation, tip off potential civil or criminal violators that are under suspicion, and/or taint the investigation such that any enforcement action is precluded from being brought."

Snare contended committee staff members are unlikely to "know all the facts" by the Oct. 3 public hearing and may reach conclusions contradicted later by other evidence. Making incomplete information public could affect witnesses not-yet interviewed by MSHA investigators, "tip off possible targets . . . and tarnish the reputation of innocent individuals."

He did not indicate who those possible targets or innocent individuals may be.

Miller replied that "the investigation will include more than just witness interviews. It will include, but not end with, Congressional hearings. And the witness interviews scheduled for [today], which the Labor Department arranged at our request, will take place."

Those interviews are with MSHA district manager Allyn Davis, the roof control specialist who approved the Crandall Canyon roof control plan, and his supervisor.

Before Miller rejected the postponement request, Snare's letter said those MSHA employees would be available "for a brief interview by your staff . . . for nonpublic interviews only."

Since disclosing the contents of those interviews could disrupt MSHA's investigation by "prematurely revealing information to other witnesses," he asked that committee staff members "take appropriate steps to ensure that such disclosures do not occur [to] avoid risks of compromising our efforts."

mikeg@sltrib.com