» Mon Jun 04, 2012 5:21 am
From UESP Wiki: "If the Markarth Guards do not warn you off after having investigated the Inn for Eltrys and you get stuck (Guards won't arrest you) when returning to him after finding out all you can about the Conspiracy, if you wander the streets and do meet the Guard who warns you off and then returning to the Temple, you will still get arrested (or attempted to get arrested)."
Ah, Wikis, gotta love them. Somewhere in that incoherent run-on sentence is a possible answer. I think it's to wander about Markarth until you find the guard with the right dialog. Be sure to check the ones inside the Keep as well as the barracks tower. http://www.uesp.net/wiki/Skyrim:The_Forsworn_Conspiracy.