Two days before it was set to hear crucial testimony, and midway through its investigation, Gov. Rick Perry on Wednesday abruptly removed three members of a state forensic science panel looking into a deadly fire for which a man was executed. Perry, acting more than three weeks after the current commissioners' terms expired, named Williamson County District Attorney John Bradley as the new head of the nine-member Texas Forensic Science Commission, replacing Sam Bassett, an Austin lawyer. The commission was scheduled to hold a public hearing in the Dallas area Friday to continue its investigation into a December 1991 Corsicana fire in which three children perished. The children's father, Cameron Todd Willingham, condemned after the fire was labeled an arson, was executed in 2004. Saying that two days were not sufficient time to familiarize himself with the case, Bradley canceled Friday's meeting. Commissioners were set to hear testimony from Baltimore fire expert Craig Beyler about his highly critical review of the methods Corsicana and state arson investigators used to determine the blaze had been deliberately set. Beyler's report, commissioned by the panel, was the third expert review to find fault with the work of fire investigators. The commission's investigation was in response to a complaint filed by the New York-based Innocence Project. On Wednesday, Innocence Project co-director Barry Scheck said through a spokesman that Perry's actions are 'like the Saturday night massacre.' He alluded to former President Richard Nixon's firing of independent special prosecutor Archibald Cox, who had been probing the Watergate scandal, in 1973. 'It seems the governor does not want the commission to promptly proceed with this investigation,' said Stephen Saloom, Innocence Project policy director. Perry's office did not respond to questions about the timing of the governor's appointments. In addition to Bassett, Perry replaced commissioners Alan Levy, head of the Tarrant County District Attorney's criminal division, and Aliece Watts, quality director of Integrated Forensic Laboratories in Euless, a Fort Worth suburb. Perry named Bradley and Norma Farley, chief forensic pathologist for Cameron and Hidalgo counties, to the panel. A third member will be appointed from recommendations provided, as the law stipulates, by a criminal defense lawyers association. Bassett, who had served on the panel four years, said he was disappointed in the timing of the governor's appointment. 'We were doing some good work. This has interrupted it,' he said. 'My fear is that the good work will be stopped by the change.' Bassett added, however, that he is optimistic that the reconfigured commission will continue the investigation. Levy said Perry's timing was unfortunate and might raise suspicions of interference with the commission 'whether they are justified or not.' 'This is a very important case and what this does is raise the temperature,' he said. 'I think the results of that are not going to be good.' The report submitted by Beyler casts serious doubt on the sophistication of techniques used by early arson investigators in the case. While the state panel is charged with considering only the soundness of the forensic procedures employed and not Willingham's guilt or innocence, the case has become a cause celebre among death penalty opponents who contend Texas executed an innocent man. Willingham went to his execution insisting he did not kill his children, the oldest of whom was 2. 'We certainly have not seen proof of guilt,' said the Innocence Project's Saloom. allan.turner@chron.com 