Crime Laboratory Unit

Introduction

The Hennepin County Sheriff’s Office Crime Laboratory has International Program Accreditation from the American Society of Crime Laboratory Directors/Laboratory Accreditation Board.  Within Hennepin County, our laboratory provides forensic services to more than 35 law enforcement agencies, the Minnesota State Patrol, and a number of state and federal law enforcement agencies. The laboratory is staffed by licensed peace officers, scientists, and civilians serving in the following specialized areas:

  • Biology Section
  • Crime Scene Section
  • Evidence Section
  • Firearm and Tool Mark Examination Section
  • Latent Print Section

The Hennepin County Sheriff's Office Crime Laboratory Unit is one of four (4) accredited crime laboratories in the State of Minnesota (the others are the MN BCA Laboratory in St. Paul and Bemidji, and the Minneapolis Crime Laboratory).  At the HCSO Crime Lab, the Crime Scene Section, which operates 24/7, was the first full-time team of crime scene investigators (CSIs) in Minnesota to earn accreditation.

The laboratory places a strong emphasis on the investigation of property crimes. Over 50% of the crimes investigated by the laboratory are related to property crimes.  The laboratory has been extremely successful in indtifying property crime offenders through the use of forensic databases (particularly the Combined DNA Index System database, known as CODIS.)

The demand for the services of the Hennepin County Sheriff's Office Crime Laboratory continues to grow.  Advancements in technology (particularly in DNA analysis) and the laboratory’s focus on property crime investigations are two of the driving factors behind the increasing demand for forensic services from suburban Hennepin County law enforcement agencies.

 

Biology/DNA Section

The Biology/DNA Section is staffed by Forensic Scientists who have received extensive education and training to examine items of evidence, identify the presence of biological fluids such as blood, semen, or saliva, and perform forensic DNA analysis on these items.

The HCSO Crime Laboratory is one of only three crime laboratories in the State of Minnesota that provide forensic DNA testing (the other two are the MN BCA Lab located in St. Paul and Bemidji).

The HCSO Crime Laboratory is one of over 190 public law enforcement crime laboratories nationwide that participate in the FBI Combined DNA Index System (CODIS). CODIS allows the laboratory to compare biological evidence recovered at crime scenes to a database of DNA profiles that include the following:

  • Convicted Offenders
    • DNA Profiles of individuals convicted of a crime
  • Forensic Samples
    • Unknown DNA profiles developed from crime scene evidence such as semen stain or blood
  • Arrestees
    • DNA profiles of arrested persons (if state law permits the collection of arrestee samples)
  • Missing Persons
    • DNA reference profiles from missing persons
  • Unidentified Human Remains
    • DNA profiles developed from unidentified human remains
  • Biological Relatives of Missing Persons
    • DNA profiles voluntarily contributed from relatives of missing persons

If certain upload criteria are met, CODIS database searches can be done on a local (LDIS), state (SDIS), or national level (NDIS).

CODIS generates investigative leads in cases where DNA evidence is recovered from the crime scene.  Matches made among profiles in the Forensic Index can link crime scenes together; possibly identifying serial offenders.  Based upon a match, law enforcement personnel from multiple jurisdictions can coordinate their respective investigations and share the leads they developed independently.  Matches made between the Forensic and Offender Indexes can provide investigators with the identity of a suspect.

Crime Scene Section

The Crime Scene Section is staffed by twelve (12) Crime Scene Investigators (CSIs) and two (2) Sergeants.  The primary duties of the section include providing 24/7/365 crime scene processing services to the Sheriff’s Office, suburban Hennepin County law enforcement agencies, the Minnesota State Patrol, and a number of federal law enforcement agencies.  

The CSIs assigned to the section are responsible for locating, collecting, and packaging evidence at crime scenes; photographing crime and accident scenes; and measuring, sketching and completing diagrams of crime scenes.  CSIs also receive specialized training in bloodstain pattern analysis, shooting reconstruction, forensic mapping, and  panoscan.

 Evidence Section

The Evidence Section is staffed by Evidence Specialists who are responsible for the intake, secure storage, and disposal of evidence received by the laboratory.  Property and evidence are secured at two locations (the evidence vault within the laboratory facility and the property storage area at the Patrol Division headquarters located in Brooklyn Park).

The laboratory accepts evidence submissions between 0900 and 1500 hours, Monday through Friday. Agencies should call ahead for submissions 612-596-7019. This will assist staff to expedite the intake process and minimize wait times for other customers.

Firearm and Tool Mark Examination Section

The Firearm and Tool Mark Examination Section is staffed by a Firearm Examiner and a Forensic Scientist.  The primary responsibilities of the section include firearm examination, tool mark examination, and serial number restoration.

The HCSO Crime Laboratory is one of many law enforcement agencies nationwide that participates in the Alcohol Tobacco and Firearm (ATF) National Integrated Ballistic Information Network (NIBIN).  The NIBIN database is a powerful investigative tool that increases the possibility of solving unrelated crimes involving the same firearm.  NIBIN allows the laboratory to compare firearm evidence recovered from crime scenes to a database of cartridge casings and bullets.  NIBIN database searches can be conducted on a local, state, or national level.

Through the NIBIN program, Integrated Ballistics Identification System (IBIS) equipment is used to compare firearms related evidence stored in the database.  IBIS digitally captures the images of fired bullets and fired cartridge cases from crime scenes as well as test fires from recovered firearms.  When a new image is entered, the system searches the existing database for a match.  When a possible match is observed, a firearm examiner must verify the match by comparing the actual items of evidence under a comparison microscope.  Once the conformation is made, a “hit” is noted in the system.  A “hit” is defined as a linkage of at least two different crime investigations where there previously had been no known connection.  NIBIN allows for links between investigations across jurisdictional boundaries.

NIBIN partner agencies and ATF work together in partnership against violent crime.  ATF purchases IBIS equipment for deployment, and provides for regular upgrades and service, as well as administering the network over which it communicates.  ATF also provides a weeklong training course for new users of the system.  In return, NIBIN partners agree to support the program with adequate staffing and resources, to enter as much firearm evidence as possible into their IBIS systems, to share evidence and intelligence information with other law enforcement agencies, and to abide by ATF regulations for use of the NIBIN system.

Latent Print Section

The Latent Print Section is staffed by Forensic Scientists whose duties include the recovery of latent prints from items of evidence submitted for processing and the comparison and identification of latent prints to known persons.

The HCSO Crime Laboratory is one of the partner agencies participating in the Midwest Automated Fingerprint Identification Network (MAFIN).  MAFIN is a shared regional database of fingerprints from South Dakota, Minnesota, and North Dakota.  MAFIN allows the laboratory to compare fingerprint evidence recovered from crime scenes to a database of known fingerprints and palm prints.  MAFIN searches can be conducted on a local, state, or national level (IAFIS).

The Latent Print Section uses a Motorola Printrak Automated Fingerprint Identification System (AFIS) terminal to link to MAFIN.  MAFIN/AFIS enables speedy comparison of fingerprints and detects matching records under alias names for all fingerprint records among the three states.  The MAFIN database also contains unknown latent prints left at crime scenes.  As new fingerprint records are added to the system, they are automatically searched against these unidentified prints.