Assisting Defense Attorneys

The polygraph examination, commonly known as the lie-detector test, can be a very useful tool to assist someone in proving their veracity/truthfulness. While polygraph examination results are not admissible in a trial, they have many other uses, both in and out of the courtroom.

Michigan appellate courts do allow judges to consider polygraph examination results in two instances:

  1. In a motion for a new trial, where the defendant seeks to introduce the polygraph results of a witness, other than the defendant, in order to show that a prosecution witness committed perjury during the criminal trial (People v. Mechura, 205 Mi App 481, 1994).
  2. On a defendant’s pre-trial motion to suppress evidence, where the defendant claims that a police officer acted illegally in obtaining the evidence. (People v. McKinney, 137 Mi App 110, September 4, 1984)

The polygraph examination can also assist the defense attorney in reaching plea bargains with the prosecution, impugning key witnesses, challenging sentencing reports, and bolstering credibility disputes.

For the defense attorney, the polygraph examination takes the unknown out of allowing their client to take a police-administered polygraph examination. It would be unwise for a defense attorney to have their client take a police-administered polygraph examination without first having the client take a private polygraph examination that was protected by the attorney’s “Work Product”. (People v. Sclafani, 132 Mi App 268; 347 NW2d 30 [1984])) In the Sclafani case, the Michigan Court of Appeals considered it to be "ineffective assistance of counsel" for a defense attorney to allow his or her client to take a police-administered polygraph examination without first checking to see how the client would do on a privately administered polygraph examination.

Defense attorneys should not overlook the utility of the polygraph examination in pre-trial and post-trial motions. The general rules prohibiting evidence of a polygraph examination in a trial do not apply to the pre-trial and post conviction stages of the proceedings.