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Home About Us Laboratory Services Scientific Analysis Questioned Documents

Questioned Documents

Questioned Documents


The Questioned Documents Unit (QDU) provides forensic support to the FBI and federal, state, and local law enforcement agencies by conducting forensic examinations on evidence collected during an investigation. This is accomplished through written reports that contain results of examinations and technical information relating to the evidence and by providing expert testimony concerning information and opinions contained in the reports, when required. The QDU also provides training to federal, state, and local forensic examiners on specialized technical topics in the forensic document discipline and assists law enforcement by providing information and presentations concerning the capabilities of the QDU and forensic document discipline in general. The QDU monitors, develops, and provides information to legal, investigative, and forensic personnel on legal issues and assists other forensic document examiners in formulating written examination guidelines to standardize procedures.

The Team

Document examiners, case processing technicians, and program managers

The Work

  • Handwriting comparisons;
  • Fractured/cut edge comparisons (paper, tape, postage stamps, dryer sheets);
  • Plastic bag comparisons;
  • Printing process examinations (document authentication/typewriting classification);
  • Charred and liquid-soaked document preservation;
  • Indented writing examinations;
  • Alternate light source examinations (ink discrimination, alterations, enhancements);
  • Office machine artifact comparisons;
  • Tire tread and shoeprint comparisons/classification;
  • Database queries (Anonymous Letter File, Automated Counterfeit Identification Database, Bank Robbery Note File, Tire Tread and Shoe Print Databases);
  • Testimony in legal proceedings; and
  • Training to counterparts in law enforcement.

To submit digital evidence for shoe print, tire tread, and bank robbery note searches, e-mail a request for search on agency letterhead and the image to be searched to the corresponding e-mail address below: