if there's one thing season 1 establishes, it's that john is scanning every newspaper in the country. he's putting patterns together and looking for cases or signs of azazel.
so there is just no way he wouldn't catch a string of mysterious murders being reported on in st. louis. and therefore, no way in hell he wouldn't also catch the follow up that a now-deceased man named dean winchester seems to have been guilty.
what did he think? does he know sam is hunting with dean yet? or did he think dean died alone on a hunt. he didn't even bother to call to double check. maybe he stalked them a bit to find out the truth?
but we'll never know. dean will never know. and heck, the next time dean is Actually dying, john doesn't bother to check in either.
