SALEM – Christopher Houghton, the Marblehead man accused of sexually assaulting his ex-girlfriend and ransacking her home in 2006, most likely will go to trial on a lack of criminal responsibility defense, according to his attorney.In Salem Superior Court Tuesday morning, Assistant District Attorney Kate B. MacDougall told Judge Howard J. Whitehead that the commonwealth is still waiting for DNA results from the state lab, which are expected on Feb. 20. Defense lawyer Robert N. Weiner asked that the case be continued to Feb. 26 for the DNA results and told Whitehead that “most likely” the defense will be criminal responsibility at the trial.Although Weiner has not actually notified the commonwealth of his client’s defense, he said he expects to do so on the next date. Defense lawyers must give a written notice to the commonwealth as to their intent for a mental instability defense so they can have their own medical experts examine Houghton for trial, which probably will delay the trial, but no actual date has yet been set down for the trial.In the early morning hours of Dec. 17, 2006, Houghton allegedly broke into his ex-girlfriend’s home on Atlantic Avenue in Marblehead and reportedly beat and raped the 19-year-old as he told her he was going to kill her and ransacked her home.When police responded to the scene after receiving a 911 call, Houghton was just pulling out of the driveway. He was chased down Atlantic Avenue before police stopped him.Authorities say he was drunk at the time, had no shoes or shirt on and was combative. His blood alcohol level was reportedly twice the legal limit.Houghton, 20, who lives with his parents at 19 Girdler Road in Marblehead, stands charged with attempted murder, two counts of aggravated rape, armed assault and burglary, indecent assault and battery on a person over 14, three counts of assault and battery with a dangerous weapon, assault and battery, operating a motor vehicle while under the influence of alcohol, malicious destruction of property and intimidation of a witness in connection with the case – allegations he has denied.He currently is on house arrest, only to leave home two days per week to work with his father at the family-owned marina in Winthrop, attend substance abuse and mental health programs, attorney appointments and court appearances.