You know what's hard to figure out here. Public domain.
Like there's this many worlds smooshed together, some with their own content and others seemingly not. And then there's whatever is already in this little pocket realm and what... Do we wing it on the copyright terms? Are there even lawyers here to try and sue the crap out of an infringement? Can I plagiarise the Hungry Caterpillar to find out?
Anyway, in the absence of decent information to cover true crime without basically ripping off Ann Rule, apparently I'm writing children's books now.