Answer:
effects of availability heuristic
Step-by-step explanation:
Availabiliity heuristic is a mental state in which a person uses examples that comes to his/her mind when examining a topic.
Just like the question shows, the past happenings (immediate or not) of gun violence has made people feel they have very low chances of survival if they are ever in that situation.
SImply put, availability heuristic means a mental state of assuming a future situational outcome from past occurences or situation.
Cheers.