In one of the last decisions of the term, the U.S. Supreme Court made it clear that criminal defendants have the right to cross-examine the forensic experts who create lab reports introduced at trial. The ruling in Melendez-Diaz v. Massachussets upholds the principal that a defendant has a constitutionally guaranteed right to confront his/her accusers.
In the past, some states had allowed the prosecution to introduce a certified affidavit indicating the results of forensic analysis into evidence without calling the technician to testify. This meant that the defendant could not question the technician about the process by which the analysis was conducted or the accuracy of the results. Now, defendants who have been notified that the state intends to introduce forensic analysis may then notify the State of his/her desire to confront the witness. The Court also made clear that althought the state must produce the witnesses for trial, it may also impose procedural rules concerning the testimony. As such, it is likely that the states will adopt rules that require the defendant to make the election to require testimony within reasonable time frames or lose the right.