District Attorney Jim Woodall said his office got the report on Tuesday, but he would likely not have a chance to review it until next week.
Woodall has said there is no indication that criminal activity led to the blaze. The report is expected to clarify the moments immediately before and after the historic building caught fire.
Investigators have determined that the fire was accidentally started by a contractor using a soldering torch. Crews were working on a $415,000 exterior renovation of the 129-year-old courthouse.