Guns are a tool with a specific design function, to kill.  When you handle guns, you can NEVER be too careful.  Even if you are a "professional", you need to double and triple check your equipment and have someone else check you again.

"The 73-year-old was there as a student in the citizens police academy, a two-hour course intended to give an intimate look at what makes the department in the quaint Florida town work. On this night, the group of 35 would tour the station and talk with officers, an essential part of academy curriculum that has gained popularity across the country amid a heated national debate about police violence.

When it came time to get involved, Knowlton volunteered."