::::I wish we'd just let people edit.  Yes, there was a lot of overlap between the articles on the suspect and the crime in this case.  As pointed out, it was only one day.  Once people refine the two articles according to WP:summary style, the uniquenesses of each will probably become apparent.  Otherwise they can be merged without controversy. 
 ::::In this case, it's apparent that the shooter has spent what he claims is nine years compiling the Templar Tl;dr Manifesto - for better or worse people are going to be going over his tactical and political ideas for a long time to come.  I think we'll need yet another article page for that.