When people in New Mexico face criminal charges, they might expect that the evidence presented in court against them is scientifically rigorous, especially if it is framed as a psychological or IQ test. However, researchers say that in many cases, this may not be true. Courts might not screen out testing protocols that are unreliable or untested, allowing pseudoscience in as evidence. The results of these tests and the analysis provided by experts could influence sentencing, pre-trial detention and other important elements of a case.

Scientists at Arizona State University examined many different psychological tests entered into evidence in American courts. They found that up to 33% had not been reviewed at all by experts in psychological journals. Of the two-thirds that had been reviewed, only 40% received positive evaluations, while 25% were explicitly judged to be unreliable. Under the federal rules of evidence, only tests that are generally accepted by the scientific community should be used in court. However, the courts often do not exclude this evidence, especially if the defense team does not raise an objection. According to the study, objections were raised to dubious tests in only 3% of cases.

This is not the first time that questionable evidence has been used against people despite a lack of scientific rigor. Many forensic techniques like blood spatter analysis, bite mark measurement and arson investigation were later proven to be inaccurate, leading to a number of wrongful convictions. After a major 2009 report, significant reforms have taken place in forensics, but problematic psychological tests continue to enter the courtroom on a regular basis.

When people are charged with a crime, they face a whole system that may be working for their conviction. A criminal defense attorney may work with people to mount a strong defense and challenge unscientific evidence offered by the prosecution.