Just finished Jarett Kobek's books, "How to Find Zodiac" and "Motor Spirit". The former is far more entertaining, an actual page-turner. It delves into maybe the most compelling suspect I've seen before in Paul Doerr. I like how Kobek frames things in a level headed fashion, he's not a sensationalist in any way.
I just looked back at the LA Mag article about the book from September 2022 which got a lot of publicity at the time. Doerr's daughter Gloria shares some pretty incriminating stories about her pops.
https://www.lamag.com/citythinkblog/zodiac-killer-paul-alfred-doerr/How to Find Zodiac is also a fascinating portrait of pre-internet zines and mail-based communities... reading through, a lot of the correspondence (and Doerr in particular) reminded me of some of the users on Slap.
I also watched the recent Peacock 2-part series, Myth of the Zodiac Killer, which suggests Zodiac was basically a letter writing campaign and these were all separate crimes and copycats. That Zodiac never really killed. That theory has some merit, but the Doerr evidence sort of blew that out of the water (although there's some reason to believe the July 4th, 1969 shooting might not have been Zodiac).
Really curious what else comes out evidence-wise about Doerr, since it's already been 10 months since the LA Mag piece.