Assertion comes as forensic science panel finishing inquiry into 1991 fire that killed Cameron Todd Willingham's 3 children.

8:47 p.m. Wednesday, Sept. 8, 2010

The State Fire Marshal's Office stands behind its controversial conclusion that Cameron Todd Willingham started the house fire that killed his three children in 1991, contradicting arson experts and scientists who insist the agency relied on bad science in its investigation.

In a pointed letter to the Texas Forensic Science Commission , which is nearing the end of a contentious review of the Willingham arson investigation, Fire Marshal Paul Maldonado defended his agency's handling of the case that led to Willingham's execution in 2004.