DENVER — Weeks before a man killed a Colorado sheriff’s deputy and wounded four other officers, prosecutors considered but declined to file criminal charges against him over angry emails he sent.

Matthew Riehl ambushed police who responded to a 911 call he made from his apartment at a Denver suburb on Dec. 31. Douglas County Sheriff’s Deputy Zackari Parrish was killed before the 37-year-old Riehl was killed by police.

Riehl began sending angry emails after he was issued a traffic citation on Nov. 10. Riehl sent more than a dozen emails to the officer who ticketed him and the municipal court.

A TV station reported that public records it obtained showed police and prosecutors considering charges against Riehl.

But prosecutors determined Riehl’s rants weren’t criminal.