Critics found fault with a government report on a deadly Utah mine collapse even before its release today.

The chairman of Utah mine safety commission says he has doubts about the Federal Mine Safety and Health Administration's ability to assess its own performance, and believes that an independent agency should have conducted the investigation.

The federal group has been privately briefing families prior to holding a news conference today to release its report on the Crandall canyon mine cave-in last August.

Federal regulators say the operator of a collapsed Utah mine violated safety protocols by cutting coal pillars that should have been left standing to prevent cave-ins.

A federal report says a subsidiary of Ohio-based murray energy corp. undermined other pillars by excavating coal from tunnel floors.

The Aug. 6 collapse trapped six miners whose bodies have never been recovered. Three others were killed during a rescue attempt.

MSHA said Murray Energy misled regulators about the dangers and violated its approved mining plan. The company says it is preparing a response.