Biology and DNA
Our forensic science lab is one of only 4 in Minnesota that provides DNA testing and forensic serology. Serology is body fluid identification that includes blood, semen, saliva, and urine.
We compare DNA profiles of a person of interest to profiles obtained from crime scene evidence.
We also take part in the FBI Combined DNA Index System (CODIS). We enter eligible DNA profiles into the CODIS database. CODIS automatically searches for possible matches with existing DNA profiles.
CODIS is a database of DNA profiles that include:
- Individuals convicted of a crime
- Profiles developed from crime scene evidence such as semen stain or blood
- Arrested persons (if state law permits the collection of arrestee samples)
- Missing persons
- Unidentified human remains
- Profiles voluntarily contributed from relatives of missing persons
Crime scene
We provide crime scene processing 24 hours a day, every day of the year.
The agencies we support:
- Hennepin County Sheriff's Office
- Suburban Hennepin County law enforcement agencies
- Minnesota State Patrol
- Some federal law enforcement agencies
Crime scene investigators:
- Locate, collect and package evidence at crime scenes
- Photograph crime and accident scenes
- Measure, sketch and complete diagrams of crime scenes
They get special training to recognize and document bloodstain patterns and ballistic trajectories. They also get special training in forensic mapping and 360 imaging.
Evidence
Evidence specialists receive evidence from law enforcement agencies. They then distribute evidence to appropriate sections of the lab for testing.
To make intake efficient and reduce wait times, agencies must schedule an appointment to submit evidence.
Schedule an appointment to submit evidence.
Firearm
Firearm and comparative examination
We use comparison microscopes to determine if:
- Bullets, cartridge cases and other ammunition components were fired from a specific firearm
- One or more firearms was used in a crime, in the absence of a submitted firearm
We also examine and test-fire firearms to determine functionality.
Serial number restoration
We use physical and chemical processes in an attempt to restore a serial number.
NIBIN
We enter evidence into the National Integrated Ballistic Information Network (NIBIN). NIBIN compares images of fired cartridge cases to previously entered images, for possible leads in investigations.
Latent prints
Latent prints are unintentional impressions that can be left by our friction ridge skin when contact is made with a surface. Friction ridge skin consists of raised ridges with furrows in between and is only found on the palmar sides of our hands and the soles of our feet.
“Latent” means hidden, so often these types of impressions are not readily visible to the naked eye without using some type of enhancement technique or additional lighting.
The Latent Print Section is responsible for:
- Processing physical items of evidence collected at crime scenes to assist in the recovery of latent prints
- Various physical and chemical techniques can be used, which include:
- Cyanoacrylate (aka superglue) Fuming
- Dye Stains
- Powders
- Analyzing and comparing latent prints recovered from crime scenes to known exemplars
- Utilizing Automated Biometric Identification System (ABIS) databases, which are large-scale repositories containing known exemplars
- Latent prints that meet certain criteria can be searched in these databases to generate candidates for further comparison
- The Section currently has access to two external ABIS databases:
- Regional: Midwest Automated Fingerprint Identification Network (MAFIN)
- Includes records from MN and ND
- Federal: FBI Next Generation Identification (NGI)
- Collecting known exemplars of deceased individuals involved in a criminal case
