Actions taken at the onset of an investigation at a crime scene can play a pivotal role in solving a case. This requires personnel who have investigative experience and specialized training in crime scene investigation. The Evidence Collection Unit is responsible for crime scene investigation in most serious crimes reported to the Harford County Sheriff's Office. Each member of the ECU has investigative experience and is specially trained in the collection, processing, and preservation of physical evidence.
Most of the crime scene investigators are certified fingerprint examiners. Fingerprint examiners compare fingerprint evidence recovered from crime scenes to fingerprint exemplars on file. Using magnifiers to better visualize the minute ridges and other features, an examination may link fingerprints found on crime scene evidence to a specific person (to the exclusion of all other persons). Fingerprint examiners also use chemical processes to visualize fingerprints. The Harford County Sheriff's Office Evidence Collection Unit is equipped with the Automated Fingerprint Identification System (AFIS) that checks latent fingerprint impressions against a statewide database of fingerprint exemplars.
The Evidence Collection Unit is also responsible for forensic analysis of video surveillance tapes. The technicians operating the video analysis computer system have been trained at the FBI Academy. The technicians can de-multiplex surveillance tapes and place the area of interest into real time. Still images can be extracted from the tape to aid in suspect identification. Members of the ECU have provided service to State and Federal agencies within Maryland and to agencies from surrounding states.