Of Guilt, Models, and Murder - S1-E5
Continuity mistake: When The Hulk breaks free of the car getting crushed look closely. You can see Lou Ferrigno's palms aren't painted green like they are usually.
Blind Rage - S3-E2
Revealing mistake: While pushing back the tank, the Hulk seems to be wearing light green loafers.
Factual error: The story takes place in Galveston, Texas. The geographical area is flat, but if you look closely near the last hulk out, there are mountains in the background.
Answer: The Hulk is accused of killing Dr. David Banner and Dr. Elenia Marks. After the lab explodes, McGee sees the Hulk emerge carrying the body of Dr. Marks, so he assumed the creature is guilty. It was McGee who caused the explosion. After following the trail of evidence of the Hulk to the lab, he hides when David and Elania arrive. In a darkened storage closet, he knocks over a bottle of flammable liquid. He confronts them, then is forced to leave by Banner, who says, "Don't make me angry, you wouldn't like me when I'm angry." When Banner reenters the lab, it explodes, caused by the Hulk when it went on a rampage trashing the lab, causing many electrical systems to catch fire, thus igniting the flammable liquid.