A boyfriend said he 'thought ' he had to kill six members of his girlfriend 's family during a Christmas Eve dinner as he took to the stand in a bid to avoid the death penalty . Joseph McEnroe , 36 , from Carnation , Washington , was convicted of slaying four adults and two children - aged three and five - in 2007 by a jury last week . The same 12 people that found him guilty of the murders are now determining whether he will be executed or sentenced to life in prison without parole . Scroll down for video . Joseph McEnroe , 36 , from Carnation , Washington , ( pictured in court on Thursday ) who murdered six members of his girlfriend 's family on Christmas Eve , 2007 , is testifying in the penalty phase of his trial in a bid to avoid the death penalty . In an attempt to spare his life , McEnroe told the court on Thursday he 'thought ' he had to kill Wayne Anderson , 60 , and Judy Anderson , 61 ; their son and daughter-in-law Scott and Erica Anderson , both 32 ; and the younger couple ’ s children Olivia , 5 , and Nathan , 3 . The court heard that McEnroe and his girlfriend Michele Anderson gunned them down and then hid their bodies in a shed behind the house . ' I know that ’ s not a good excuse ' he said . ' I ’ m not trying to excuse myself . I ’ m trying to explain my actions . 'There is no question I did these awful things . I thought I had to . ' During his testimony , according to KIRO-TV , he claimed he was abused as a child at the hands of his unstable mother and her boyfriends . Wayne and Judy Anderson ( pictured ) were the first to be killed by Joseph McEnroe on Christmas Eve 2007 . McEnroe had been living with his girlfriend in a mobile home in the backyard at the time . Erica and Scott Anderson ( pictured ) and their children were also shot and killed during the holiday gathering . According to The Seattle Times , he was constantly interrupted by the prosecutor or court reporter , asking him to speak up or slow down . At one point he started giggling and had to apologize to the court room for his 'terrible ' speech impediment . He added : ' I did not do this because I wanted to . I was trying to protect Michele . I was completely wrong . Anderson had been living in a mobile home with McEnroe on her parents ' property and prosecutors said the couple was upset Michele 's parents did not pay their rent . The defense called Dr Donald Dutton , a professor of psychology at the University of British Columbia , who said McEnroe was a victim of 'folie à deux . ' Michele Anderson , McEnroe 's girlfriend , is set to stand trial for the brutal killings later this year . Court hearings have been delayed because of concerns over her mental capacity . Because he had shared a home with Anderson , Dutton explained , McEnroe had become to believe her claims she had been sadistically abused by her father . Anderson will face trial for the killings later this year , but court hearings have been delayed over questions regarding her mental competency and whether she is fit to stand trial . If the jury decides on the death penalty , McEnroe would be the first person sentenced to death in King County since 2010 . There is currently a moratorium on executions while Washington Governor Jay Inslee is in office .
Joseph McEnroe , 36 , was found guilty of six murders last week . Slayed four adults and two children in Carnation , Washington , in 2007 . Was staying behind the house with girlfriend Mumbled at the time . Jury is deciding whether he is jailed for life or is condemned to death . Michele Anderson and giggled as he testified in a bid to avoid execution .