(CNN) -- An advocate for the family of Cameron Todd Willingham, executed six years ago after a fire killed three of his daughters, is sharply questioning the objectivity of the head of the Texas commission looking into whether the man was rightly convicted. Stephen Saloom, the policy director of the nonprofit legal advocacy group the Innocence Project, brought up a comment attributed last week to John Bradley, chairman of the Texas Forensic Science Commission, during the public comments portion of that panel's meeting Friday. According to the published report, Bradley said that anti-death penalty groups wanted to hold up Willingham -- convicted in 1992 after a jury determined he deliberately set the fire that killed his three girls -- as a "poster boy" for their cause. Bradley questioned that approach, calling Willingham "a guilty monster."
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NEW: Texas board members in heated exchange over whether man wrongfully executed
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Jury convicted Cameron Todd Willingham after finding he set fire that killed three daughters
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Legal advocate questions the objectivity of the Texas board's chairman
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Panel's chairman calls criticism "personal attacks" and says, "We're being used"
At Friday's hearing, Saloom noted "concerns" about several moves that Bradley had made and questioned whether it was necessary to "revisit everything" that the commission had done prior to @placeholder's appointment.