Three years after Christa's murder, investigators decided to take drastic measures. They collected swab samples of as many Truro men as possible, hoping that they would find a genetic match with the evidence found at the crime scene. Hundreds of men volunteered to help out in the case by offering their DNA, but many also refused because the sample collection was not mandatory.
Some of the area residents argued that the entire process of collecting swabs was unnecessary, since it was unlikely that the murderer would willingly volunteer evidence that would later implicate him. Furthermore, the crime lab had not yet finished processing all of the DNA samples taken from the original suspects because their resources were overtaxed and they had not enough time to examine them. Thus, it made little sense to overburden them even more with hundreds of new samples. It was clear that the state was desperate to show that they were still working hard on the case and trying to find the killer, regardless of how irrational some found their methodology to be.
After all the fuss, the crime lab never got a chance to process the new samples. Surprisingly, an earlier sample obtained in March 2004 turned out to be a genetic match with semen collected at the crime scene. It was the big break investigators were hoping for in a three-year-long investigation. The man who voluntarily provided the police with the DNA sample was identified as Christopher M. McCowen, 33, a garbage collector, who worked in Christa's neighborhood at around the time of her death.
CBS correspondent Sharyn Alfonsi reported that investigators were interested in testing McCowen because he "had a lengthy criminal record." His previous record included several restraining orders on Cape Cod involving five women and he had even served time in a Florida prison for a variety of other offenses, the Hartford Courant reported. Some of those offenses included car theft and burglary.
As more facts emerged, investigators discovered that three years before McCowen gave the sample, he was actually interviewed by police concerning the crime. However, he didn't provide a DNA sample then and managed to elude police by moving frequently within a two-year period, the Associated Press reported. The police finally caught up with him and were able to finally obtain his DNA, but it took another year for the sample to be processed and matched to that taken from Christa.
On April 14, 2005, the police arrested McCowen at his home in Hyannis. He was charged with first-degree murder, aggravated rape and armed assault. The Associated Press quoted Michael O'Keefe, who said that "investigators certainly have a motive," although they refuse to state what it is. McCowen, who pleaded innocent to the charges in Orleans District Court, was held without bail.
It is not clear when the case will go to trial, but in the meantime, Christa's family refuses to sit back and wait. They are currently in the process of suing McCowen and Cape Cod Disposal Co. for $10 million for employing McCowen even though he had a criminal record, the Associated Press reported in a May 2005 article. The report suggested that compensation, if awarded, would likely go to Ava.