Character mistake: It's more than unlikely that a prison guard would leave a suspected murderer (George) alone with anyone, especially a woman (Edna) for minutes. (00:24:28)
Character mistake: When first discussing the projectile Murdoch has written on his board that 2 (sin45) =1. This is obviously incorrect to anyone who's studied even basic trigonometry. (00:05:54)
Answer: It's certainly a personal choice about using one, and probably similar to how some people refuse to wear a helmet or forego other safety equipment. Most bells and horns on bikes are not very loud and probably wouldn't be heard in busy traffic, making them mostly ineffective. Murdoch would likely still yell, even if he had a bell or horn.
raywest ★