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Police Department

Technical Investigations Section

Lieutenant Frank Ragains

Lieutenant Frank Ragains

(615) 862-7826

The Technical Investigations Section (TIS) is part of the Investigative Services Bureau. This section is staffed 24 hours a day. Every TIS investigator is trained in the documentation, collection and preservation of all manner of physical evidence. This can be (but is not limited to) a fingerprint, footprints, tool impressions, blood or semen, trace evidence (hair or fiber), or even tire impressions. These small, seemingly insignificant, pieces of evidence can be paramount to identifying a suspect and bringing him to justice. Many of the TIS investigators have attended specialized training schools from the FBI, TBI, ATF, DEA, and many universities throughout the southeastern United States. Some examples of these schools would be handwriting analysis, laser enhanced latent prints, chemically enhanced latent prints, specialized photography, buried body recovery, blood stain pattern analysis, fingerprint comparison, digital photography, tire and foot print evidence, practical homicide and death investigation, modern fingerprint development techniques and many more.

The Technical Investigation Section also has a latent processing lab. Evidence that cannot be processed in the field is brought to the lab where a wider variety of chemical processes can be administered. The lab has a processing garage where several vehicles can be secured at a time. Because of the fragile nature of physical evidence some vehicles are brought here, out of the weather, and maintained in a controlled environment while awaiting processing. The TIS is also equipped with a complete mobile lab and support vehicle to respond to the scene itself.

The Technical Investigation Section also includes the Firearms Unit operating IBIS (Integrated Ballistic Identification System). This computerized equipment allows technicians to examine firearm shell casings and bullets from crime scenes and enter them into IBIS for comparison. The computer stores the entered data and continually checks against all new entered data in order to determine if a particular weapon was used in more than one crime. A ballistic recovery system allows technicians to test fire recovered weapons, retrieve the fired bullets and shell casings and enter these "known" items into IBIS for comparison against any ballistic evidence recovered at the crime scene.

Officer using the IBIS equipment