The evidence is sent to the labs to be tested and examined. There are many different labs. Those are the fingerprint analysis lab, the fire lab, the ballistics lab, the trace evidence lab, the hair and fiber lab, the DNA lab, the toxicological lab, the questioned document lab, and the digital evidence lab.

The fingerprint analysis lab involves taking evidence and using fingerprint powder and chemicals to develop and lift fingerprints. The prints are then lifted and/or photographed and compared against other prints in AFIS to determine who the questioned fingerprint belongs to.

Questioned fingerprints are those that are found at a crime scene. The fingerprints are unknown and examined to determine the type of fingerprint and who the print belongs to. The types of fingerprints are Loops, Arches, and Whorls. The subtypes are Radial loops, Ulnar loops, Plain arches, Tented arches, Plain Whorls, Double-loop whorls, Central pocket whorls, and Accidental whorls.

The fire lab deals with fire debris and determining where the fire started, why it started, when it started, what started the fire, who started the fire, and how to prevent it in the future.

The ballistics lab focuses on studying and examined firearms, shell casings, striation markings, tool marks, and even bullet holes to determine whether the suspected weapon was used in a crime.

The trace evidence lab involves evidence such as hair on a shirt, a cigarette butt, or even a piece of glass. These items are available in a small amount. These items would go in a bindle. A bindle is called a druggist's fold, which is where the bottom of the bag is sealed, and the top folds to allow the trace evidence and prevent the evidence from falling out.

The hair and fiber lab are similarly interlaced with the trace evidence lab. Hair and fibers are examined to determine the type, color, length, material, and texture in respect to the evidence that is being examined. The suspect can be determined by tracing the hair and fiber samples to the individual that left it behind.

The DNA lab involves examining mostly bodily fluids such as blood, semen, and saliva. The DNA elements, such as ribose, nucleus, mitochondria, adenine, guanine, cytosine, and thymine. This also involves determining whether an object has DNA or RNA. DNA stands for Deoxyribose Nucleic Acid and RNA stands for Ribose Nucleic Acid. DNA has two, interlocking, strands that make up a twisted ladder formation, while RNA is only one strand and the thymine changes to uracile.

The toxicological lab involves alcohol and drugs. These are examined and tested to determine what the suspected item is, and how it relates to the crime, as well as who used the alcohol and drugs.

The questioned document lab examines documents to determine what the ink type is, the writing style, and how to determine whether the person of the questioned document wrote the document. A questioned document is one that is found at a crime scene. It is compared against the known document. A document can be a letter, note, a piece of mail, or even a ransom note. A ransom note is one that is written to detail what is expected or else the victim, or the family/friends of the victim, or both will suffer the consequences stated in the note.

The digital evidence lab examines and reviews electronics that are suspected to have been used in a crime. These are mainly online crimes, such as hacking. The computer, phone, or other electronic device is reviewed to determine who committed the crime, from where, and how, as well as what was hacked and the system that was used to complete the hacking.