I read on the Daily Maul last week that the coroner doesn’t rule out suicide as the cause of death.
http://www.freerepublic.com/focus/f-news/3336516/posts
"The subject said he was a 'retired police officer' and threatened to harm all of the Task Force members, as well as all of the other investigators involved in the death investigation of Fox Lake Police Lieutenant [Charles Joseph] Gliniewicz," the Sheriff's Office said in a news release today. "These threats included Coroner Rudd and Coroners Office employees, unless all the involved personnel declare Gliniewicz death a suicide."