Courts in Oregon and throughout the United States are only supposed to rely on evidence that is considered to be reliable. However, research has shown that many psychological and IQ tests that are admitted into evidence are inaccurate or based on junk science.
A study that was recently published in the Psychological Science in the Public Interest found that only one-third of tests used in criminal cases were reviewed by prominent manuals. Of those that were reviewed, less than half were given favorable grades, and only one out of every four were deemed to be unreliable.
According to the National Research Council (NRC), unreliable test results could result in people being convicted of crimes that they didn’t commit. If the accuracy of a test is in doubt, its results could be grounds for an appeal. However, research has indicated that appeals based on unreliable tests occur only 3% of the time.
In the past, those who sold tests to schools and other clients would include their accuracy rates in marketing materials. However, one professor that would receive catalogs from vendors said that these figures haven’t been included for decades. Therefore, it is hard to determine whether a test that is being used in court can say anything useful about a person’s guilt or innocence.
Among the tests that are introduced at trial, the Rorschach test and Minnesota Multiphasic Personality Inventory are used the most. The Rorschach test has been criticized by scientists as being subjective and vague while the Minnesota Multiphasic Personality Inventory has obtained positive reviews.
If you’ve been charged with a crime, consider retaining a criminal defense lawyer to help with your case. He or she may dispute the legitimacy of tests or other evidence used in court against you.