Sorry if repeated info:
"Detectives learned that Tester had a 17-year-old girlfriend who he allegedly assaulted the day before the murder.
During the last week of 2016, detectives received information from a friend of Radavich. The friend said that Radavich confessed to killing Tester during a phone call he had recorded and provided a copy of the call to detectives.
During the call, the man - identified as Radavich by the friend - said that he killed Tester because Tester was abusing his 17-year-old girlfriend and he had to take care of it by killing Tester.
Detectives also learned that Radavich was an ex-boyfriend of the 17-year-old female and she contacted Radavich after she was assaulted by Tester on September 5th."
http:// www.krtv.com/story/34197180/suspect-arrested-in-the-murder-of-robert-tester