It's true that animals cannot talk. However, animal DNA collected at crime scenes is quite telling. Crime scene investigative (CSI) units rely on information found from either a victim's or suspect's pet. During an assault case, the victim's dog relieved itself on the attacker's car. Police took a urine sample from the car and matched it to the dog's DNA. Thanks to this evidence, prosecutors were able to convict the attacker.

In another case, a serial murderer lived with half a dozen cats. Police found two bodies next to the house of the serial killer. The killer confessed that he buried other women nearby, but would not say where. The detective from the CSI unit collected hair from the cats, because the hair they shed often attaches itself to bodies and clothing. K-9 dogs picked up the scent of the cats' hair and found the bodies, putting the criminal behind bars.

CSI personnel can also be called Ets (evidence technicians), CSTs (crime scene technicians), SOCOs (scenes of crime officers), and CSAs (crime scene analysts). Regardless of job title, CSI personnel gather evidence by examining, identifying, documenting, and collecting physical clues at a crime scene.

They usually start out with at least a year as a police officer, so they have to attend police academy. Many can go straight from high school; some tend to go to college for either a two- or four-year degree first. A background in biology and forensic science is important.

People applying for this job must have strong stomachs. Being around corpses and crime scenes is not for the weak of heart. However, the work is quite rewarding because you help solve crimes. Salaries are on par with that of police detectives. Starting salary can be anywhere from $25,000 to $50,000, depending on where you live.