DUI and Discovery: The Prosecution’s Obligation

Clients often ask us what we plan on doing at trial to win their DUI case. It is important to understand, however, that prior to going to trial or arguing a pre-trial motion your attorney must have a firm understanding of all of the circumstances surrounding your arrest, the results of the chemical tests which caused you to be charged with DUI, and the analysis used to get those chemical results.

You may know from my previous writings that discovery is the process of finding or learning something that was previously unknown about your criminal or civil case. In Pennsylvania, the rules of criminal procedure (Rule 573) requires that the prosecution produce all evidence that is material to a defendant’s guilt. The Rule specifically requires the prosecution to produce:

  • The defendant’s prior criminal record
  • The circumstances and results of any identification of the defendant by voice, photograph, or in person identification
  • Results of any scientific tests, expert opinions, and physical or mental evaluations
  • Documents, photographs, fingerprints, or other tangible information
  • Transcripts or recordings of any electronic surveillance and the authority used to make those recordings

In addition to the rules of criminal procedure, the United States Supreme Court case of Brady v. Maryland, 373 U.S. 83(1963) requires that the prosecution produce any evidence favorable to the accused which either exculpates the person or that could impeach any witness at trial (attack the witnesses credibility). In addition to the Brady decision there is also a Pennsylvania Supreme Court case of Commonwealth v. Marinelli, which requires the prosecution produce “any evidence that might have affected the outcome of trial”. In a DUI case it is important that your attorney request the following information at discovery:

  • Any information related to the stop of your vehicle
  • Any information related to your performance of field sobriety tests
  • All information related to chemical tests which would include the time the test was administered, the results of the test, and the copies of calibrations and certificates the devices (Breathalyzer) used to administer the test;
  • The qualifications of the test operator;
  • Any recordings of the stop, test administration, or field sobriety tests (MVR-Motor Vehicle Recordings)

In addition to the Supreme Court’s decision in Brady v. Maryland it is also important that your attorney have a strong understanding of subsequent Supreme Court decisions regarding discovery which state that there is no distinction between eidence that is either exculpatory or that could serve as the basis for impeachment for a witness. See United States v. Bagley, 473 US 667 (1985); Giglio v. United States, 405 US 150 (1972).

Discovery is a very important part of your DUI trial and your attorney must know what the prosecution is obligated to produce in order to effectively defend your interests. Discovery violations are serious and if the prosecution fails to produce requested discovery it could result in the dismissal of charges against you.