I try not to wish or meditate on evil happening to another person, but occasionally, I will hope that they get back what they put into the world.
@RickiTarr
I found that wishing/imagining bad things happening to other people, even evil people, caused me mental distress - aka, I got more depressed.
I found a workaround, though. Instead of wishing bad things on them, I wish/imagine good things happening to all the people they hate. There's a back-of-the-head feeling of "this would really hurt that evil person!" while I'm imagining a better future.
Strangely, it works for me.