Other mistake: When Johnny brings the officer who was shot into the ER, as soon as he's loaded onto the gurney Carol takes his BP then tells Brackett his BP, but she also tells him that his pulse is 120, even though she never took his pulse. Additionally, when Morton places the blood vials on the tray and tells the nurse, "I want this sent to the lab STAT, type and cross match, and CBC and differentials STAT," due to the urgency of the situation, but the nurse doesn't leave, she just stands for the rest of the scene.
Other mistake: When John, Roy, and Vince grab the officer who was shot by the sniper and make a run for it, as they duck behind the car, right behind them we can see a city bus just driving on by the lot, directly in the sniper's line of fire, even though that area's supposedly closed off with heavy police presence.
Answer: I believe you are speaking of the old man, Mr. Wilson. He's played by J. Pat O'Malley.
Bishop73
Correct, it was J. Pat O'Malley...he also played the grandfather with his grandson when their rocket exploded, and also played "Old Bill" in the episode with Ann Prentiss, where Gage saves the little girl from the burning tree house, and her mother falls in love with him.