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DNA for the Defense Bar

NCJ Number
Date Published
June 2012
192 pages

This guide provides defense attorneys with the information and guidance they need in preparing for a trial or post-conviction proceeding that raises issues related to DNA evidence.


Information is provided on the biology of DNA and proper collection procedures for DNA evidence. The processing of DNA evidence encompasses procedures at the crime scene and laboratory testing. The interpretation of DNA analysis and findings includes a discussion of the evaluation and defense response to DNA evidence. The rationale and procedural timing for the use of an expert witness on DNA collection and analysis are addressed. A section on pretrial preparation considers whether the defense should request DNA testing, issues related to DNA collection, evidentiary issues, statistics issues, the presence of the defendant's DNA in the databank, and issues of hearsay and confrontation related to DNA evidence. Other trial issues addressed pertain to the jury, the opening statement, witness preparation, and objections during the State's direct examination of a DNA expert, and effective cross-examination of a DNA expert. A section addresses delayed prosecutions, cold-case DNA "hits," and the use of CODIS. The report concludes with a section on proactive uses of DNA in establishing third-party guilt, seeking post-conviction DNA testing, and determining when the defense is entitled to post-conviction DNA testing. 2 tables, 25 figures, and 9 appendixes with sample forms, a sample DNA analysis, and additional references on statistical issues in DNA identification

Date Published: June 1, 2012