Check out the following 3 hiders and notice something.

[hider=“People don't kill. I do.”]
The apostrophe and all the text behind it disappears.[/hider]

[hider=“People dont kill. I do.”]
Nothing happens.[/hider]

[hider='People don't kill. I do.']
All the text disappears.[/hider]

In addition, posting a new thread with hiders initially breaks them. You need to edit the post and save it again in order for the hiders to show up.