During a hearing in Freehold, New Jersey, Paul Caneiro stood before Superior Court Judge Marc C. Lemieux on March 4. A New Jersey judge has allowed prosecutors to utilize a sophisticated DNA tool in the upcoming trial of a man accused in the 2018 murder of four family members. Monmouth County Judge Marc Lemieux concurred with prosecutors that STRmix, a cutting-edge DNA analysis tool capable of examining small and complex DNA samples that would have been challenging to analyze in the past, has proven to be reliable after rigorous testing. Lemieux stated in a 212-page ruling that “STRmix is effective and appears to perform exceptionally well.” Defense attorneys for Paul Caneiro, charged with the murder of his brother and his brother’s family, had requested the exclusion of evidence obtained using STRmix, arguing that its suitability for use in criminal proceedings had not been adequately confirmed. Caneiro, aged 51 at the time of the murders, has pleaded not guilty to first-degree murder charges in the deaths of Keith Caneiro, 50; Jennifer Caneiro, 45; and their children, Jesse, 11, and Sophia, 8. The victims were discovered in their Colts Neck home on November 20, 2018, approximately 47 miles south of New York City. Prosecutors allege that Caneiro shot his brother, stabbed his niece and nephew, then shot and stabbed his sister-in-law before setting their house on fire. Following this, he allegedly set his own house ablaze in an attempt to conceal the crime. Jury selection for the trial is scheduled to commence in May. Prosecutors presented over a dozen DNA samples using STRmix in the case. Developed by scientists in New Zealand and Australia, the software has been in use in the United States for around a decade and has transformed DNA analysis procedures. Forensic experts believe that a majority of forensic labs in the U.S. currently utilize this software, which applies statistical modeling to analyze complex samples, even those as small as a few cells left on a surface. In one notable instance in the Caneiro case, traditional DNA analysis methods failed to yield results when examining bloodstained jeans found in Paul Caneiro’s basement. However, after implementing STRmix, the software indicated that the DNA on the stain was 2.7 septillion times more likely to belong to Paul Caneiro’s nephew than anyone else, as stated by a forensic analyst during the hearing. Caneiro’s defense lawyers raised concerns about the software, asserting that it lacks the same level of reliability verification as safety-critical systems used in vehicles and aircraft. In a brief, they argued that STRmix could produce erroneous outcomes that might lead to wrongful convictions.
