DOUGLAS COUNTY, Colo. - New documents obtained by KRDO NewsChannel 13 show Matthew Riehl, the gunman who blasted out more than 100 rounds onto Douglas County deputies New Year's Eve, had a mental breakdown just weeks before the attack.
The report indicates, Riehl's brother said he was diagnosed with bipolar disorder and suffered a 'manic breakdown'.
Riehl's mother, Susan Riehl said he moved out this past July and was last known to be working at a Walmart in Highlands Ranch. She told police her son had stopped talking to his family, except for strange emails.
A supervisor at that Walmart told investigators that Riehl walked off the job and filed a complaint against the store.
Report sources also said Riehl would use his law degree to intimidate people and threaten lawsuits. Some of those threats were made on social media and didn't go unnoticed.
"Several of the guys had contacted me and said 'things don't seem to be going right. He's got a website and he's been putting up some crazy stuff up there, would you get ahold of him?" said Leon Chamberlain, Riehl's colleague in the National Guard.
Susan Riehl also said her son suffered from post-traumatic stress disorder from his time serving in Iraq from 2009 to 2010. Following his deployment, Riehl refused to take his medication to treat his condition.
"Riehl's mother did contact Lone Tree police to get him help and later learned he filed a false police report stating his mother and brother were in a suicide pact," according to the report.
This bizarre behavior was all reported in October, just two months before the attack.
"That's still a brother, a brother veteran, so number one I wanted him to get help and number two I didn't want others to be at risk," said Chamberlain.
University of Wyoming police warned Lone Tree police about Riehl weeks before the shooting after he made a series of threats against UW law professors and posted anti-police rants online.
For more on the documents, click here.