There is a tomcat who was fighting my Cinder every time I let her into
our backyard. The group consensus was to trap the tomcat and have him
neutered.

Here's the story to date. Read the diary.
http://www.catster.com/pet_page.php?j=t&i=140147

I'm aware of the cat overpopulation problem but I still feel guilty
about this. I feel really bad. If he has an owner, the owner will have
4 days to reclaim him before the neutering. All he has to do is phone
the Humane Society. But somehow I feel guilty about this. I don't own
the cat and I'm cutting its balls off.