State Police Headquarters Modified Services/Hours
  • Announcement for New Pistol Permit Applicants Only - 5/26/2021
  • Effective June 15, 2020, DESPP-HQ Fingerprint Identification Unit will re-open for in person fingerprinting requestsby appointment only. - 6/5/2020
  • Effective June 15, 2020, DESPP-HQ Reports and Records will re-open for in person requestsby appointment only. For information or to schedule your appointment please click HERE - 6/5/2020
  • At this time, pistol permit renewals will continue to be done by mail only.
  • Fingerprinting Limitations and License Expiration/Renewal extensions; view documentHERE- 4/30/2020
  • Suspension of requirements for unarmed security guards from other states; view documentHERE- 4/30/2020
  • Still regular business hours for Sex Offender Registry and Deadly Weapons Offender Registry- 4/30/2020
  • No service for guard cards (see Governor Lamont’s Executive Order changes to licensing requirements HERE )- 4/30/2020
  • Individuals will be asked to wait outside until called into the building- 4/30/2020

Welcome Message

The Division of Scientific Services (DSS) provides forensic support to local, state and federal agencies throughout Connecticut.  This division is divided into three analytical Sections. They are the Chemical Analysis Section (including toxicology, controlled substances, and arson), the Forensic Biology/DNA Section, and the Identification Section (including computer crimes). The laboratory also has two non-analytical Sections.  They are the Quality Section and Laboratory Support Services (including Administration, Evidence Receiving, and Case Management).

The Division is led by a Director and each of the three sections is headed by a Deputy Director.  Reporting to the Deputy Directors are various titles consisting of Forensic Science Examiners, Chemists, Laboratory Assistants, Evidence Control Officers and State Police Sergeants, Detectives, and Troopers. The Quality Section is comprised of the Quality Assurance Manager and the Forensic Biology and DNA Quality Assurance Manager. The laboratory support area is managed by the Scientific Services Laboratory Administrative Manager.

Evidence Receiving Unit

The Evidence Receiving Unit of the DSS is the first point of contact for all agencies submitting evidence to the Laboratory.  This Unit plays an integral role in maintaining the proper storage and chain of custody of all evidence.  The submitting agencies are divided between local, federal and state agencies.  The majority of cases submitted to the DSS are from local agencies. The Division of Scientific Services has performed testing for out of state agencies in the areas of arson, GSR and video analysis in special cases and circumstances. 

The majority of forensic cases submitted to the Division of Scientific Services consist of evidence for Forensic Biology/DNA, Toxicology/Controlled Substances, Latent Prints, and Firearms examination. These cases are derived from sexual assaults, property crimes, homicides and DUI related incidents.  A significant amount of analysis in the DNA Unit is comprised of convicted offender samples for CODIS (Combined Index DNA Identification System). 

Case Management Unit

Under the direction of Governor Malloy, agencies were tasked to initiate the LeanCT approach to eliminate waste and inefficiency in their work processes.  The Case Management Unit was created in 2013 as a LeanCT initiative.  This Unit’s main goal is to act as the primary conduit between submitting agencies and the forensic examiners.  The Case Management Unit communicates with the submitting agencies for additional information or samples to complete analysis on the cases.  This Unit is also in communication with the State’s Attorney’s Offices regarding cases requiring expedited casework, pending trials or dispositions, and Discovery/Freedom of Information Act (FOIA) requests. 

The Case Management Unit currently coordinates the flow of casework to the Forensic Biology/DNA Section and has begun expanding its case management coordination to the other units within the DSS. The creation of the Case Management Unit has allowed examiners to focus on performing examinations and analysis instead of administrative duties.  The Unit has also prioritized cases according to pending court dates, arrests or other circumstances. 

Forensic Biology Unit

The Forensic Biology Unit examines evidence collected in sexual assaults, homicides, assaults, robberies, and property crimes. The Unit identifies the presence of blood, semen, and other body fluids, such as fecal material, saliva, or urine.  In addition, examiners collect samples from objects for “touch DNA” examination.  The forensic examiners in this Unit also use their training and experience to determine which samples will be forwarded to the DNA Unit for further analysis.  The types of evidence examined by this Unit may range from swabs, bloody weapons, clothing and bedding to larger bulkier items.

Pieces of evidence routinely received and screened by the Forensic Biology Unit include ‘CT 100’ Sexual Assault Evidence Collection Kits.  On October 1, 2015, the CT General Assembly enacted Public Act No. 15-207 (An Act Concerning Evidence in Sexual Assault Cases).  Per the Public Act, law enforcement has 10 days from date of collection to submit sexual assault kits to the DSS.  In turn, the DSS has 60 days from date of collection to test the sexual assault kits. 

Efforts have been made to streamline and eliminate redundancy of paperwork, documentation and analyses.  The Forensic Biology Unit currently prepares all of the extraction samples for DNA testing.  They will also examine submitted hairs located in a case for human origin determination and for the presence of an attached tissue fragment.  Human hairs with tissue are forwarded to DNA for analysis.  This ensures that the best forensic samples are being forwarded for DNA testing.

DNA Unit

The DNA Unit is comprised of three sub-units. They are the Nuclear, Database, and Mitochondrial DNA Units.  DNA stands for deoxyribonucleic acid, which is the genetic material that determines who people are, both as individuals and human beings.  DNA is located in the nuclei and mitochondria of cells, and can be isolated from various body fluids and skin cells sloughed from our bodies.  The Nuclear DNA Unit uses the type of DNA found in the nucleus of the cell.  The majority of casework analyzed by the Nuclear DNA Unit utilizes STR (short tandem repeats) analysis which has a high power of discrimination, can be automated, and successfully utilized with degraded samples. 

Each DNA case may be comprised of multiple requests depending on the type of samples submitted and the type of DNA required to generate the most probative genetic information. 


The DNA Nuclear Unit’s enters DNA profiles generated from evidentiary samples into CODIS (Combined DNA Index System) to generate matches (hits) to convicted offender DNA profiles as well as DNA profiles from other criminal cases.  Eligible profiles from forensic samples and CT convicted offenders are uploaded to the national database for searching against other state databases.

The DNA Database Unit’s primary purpose is to process convicted offender samples and upload the DNA profiles generated from these samples into CODIS.   

CODIS has multiple levels where DNA profiles can be stored and searched: the local level (for city and county DNA laboratories), state level and national level. Data stored at the state level is kept in the State DNA Index System, or SDIS. At the state level, an analyst can try to match a DNA profile from a local crime scene sample (also known as a forensic unknown) with an offender's profile within the state to solve cases that span throughout Connecticut. Data stored at the national level is kept in the National DNA Index System, or NDIS. At this level, an analyst can try to match a DNA profile from a local crime scene sample (also known as a forensic unknown) with an offender's profile from across the nation to try and solve cases that span various states.

The DNA Unit reports two types of hits. They are Offender Hits and Forensic Hits.  Offender Hits are a match of a genetic profile from evidence to a known sample submitted from a convicted offender. A forensic hit is defined as a match between two forensic evidence samples from different cases, which include unidentified remains and missing persons.  Forensic hits may provide the submitting agencies with an investigatory lead or can be used to track or establish serial-type crimes.

In addition, CODIS includes indices to aid in the identification of missing persons and unidentified human remains.  In conjunction with nuclear DNA, these indices incorporate mitochondrial DNA.

Mitochondrial DNA (mtDNA) analysis is evaluated or analyzed when nuclear DNA analysis is not feasible. Such cases include unidentified remains in which bones have been located, or in cases in which a hair is present with no tissue-like material.   Mitochondrial DNA testing traces a person's matrilineal or “mother-line” ancestry using the DNA profile from the mitochondria.  The Mitochondrial DNA profile is passed down by the mother, to all her children.  As a result, forensic comparisons can be made using a reference sample from any maternal relative, even if the unknown and reference sample are separated by many generations.  For this reason, mitochondrial DNA can play an important role in missing persons and unidentified remains investigations, mass disasters and other forensic investigations involving samples with limited biological material.

In the case of hair examinations, the Forensic Biology Unit will examine the macroscopic and microscopic characteristics of hair, and determine if the hair is human or animal.  If human, the Unit may determine if the hair was forcibly removed or naturally shed, and if the hair is cosmetically treated, damaged, or diseased.  The Forensic Biology Unit will also determine if a tissue fragment is present.  A hair will be sent to the Mitochondrial DNA Unit for further analysis if it has been deemed unsuitable for nuclear DNA testing.

In 2013, the DNA Unit developed a separate laboratory area and workflow to handle database convicted offender samples and “knowns” submitted for cases analysis.  The separate laboratory area and workflow allows the database samples and “knowns” to be processed quickly and minimizes the possibility of cross transfer with evidentiary samples.  “Knowns” are a forensic term used to describe a sample (blood or buccal) submitted from a known individual for comparison or elimination purposes.  In the case of a property crime, the “knowns” may be from homeowners for elimination purposes.  Due to the increased communication with the submitting agencies, there has been progress in the submission of elimination “knowns,” which has improved comparisons in DNA casework and has also eliminated the entry of profiles into the CODIS Database that may not be probative. 

Chemistry Unit

The Chemistry Unit of the DSS analyzes evidence involving hit-and-run, fire debris, gunshot residue (GSR)-related and explosive-type cases. Paint (usually automotive), ignitable liquid, and elemental examinations within GSR kits are the most common types of requests that are received within that unit.  A combination of classical wet-bench chemical techniques and instrumental analyses can be used within each case. 

Examiners are asked to analyze paint evidence from cases which usually evolve from hit-and-run incidents or other related investigations. They participate in a collaborative effort in maintaining the Paint Data Query (PDQ) database which is housed and overseen by the Canadian Royal Mounted Police (CRMP). State and local law enforcement agencies investigating hit-and-run homicides and other cases rely on the Chemistry Unit’s accessibility to, and expertise within, the PDQ database.  The PDQ contains approximately 20,000 samples of paint systems, which represent over 74,000 individual paint samples from vehicles dating from 1960 to the present.  This database assists law enforcement agents in their investigations of cases by providing the list of possible years, models and makes as the source of evidentiary paint samples.  The primary instrumental techniques used for paint is a combination of microscopy and Fourier-transform infrared spectrophotometry (FTIR).

Another function of the Chemistry Unit is to examine evidence for the presence of particles consistent with gunshot residue (GSR).  Evidence is usually submitted in the form of GSR kits and includes swabbings taken from law enforcement.  Clothing can also be submitted in order to determine if an individual may have been in close proximity of a recently discharged firearm.  Evidence is examined by a technique called scanning electron microscopy using energy dispersive X-ray spectroscopy (SEM-EDX).

Suspected arson and other cases involving ignitable materials are analyzed within the Chemistry Unit.  A technique called headspace analysis is utilized to remove volatile chemicals from evidence.  Such chemicals are trapped and subsequently analyzed by gas chromatography/mass spectrometry (GC/MS) in order to identify chemicals/material which may have been used to either start or accelerate fires.  The Chemistry Unit assisted with ignitable liquid sample preparation for the Department’s Canine Training Unit. 

Toxicology Unit

The Toxicology Unit analyzes blood, urine, and other body fluids in support of driving under the influence (DUI), drug-facilitated sexual assault (DFSA), and postmortem cases in support of local, state, and federal agencies.  The unit has worked with hospitals and the CT Poison Control Center network in cases involving drugs of abuse or other substances.  The majority of work within the unit involves analyzing ante mortem samples (e.g., urine, blood) for the presence of ethanol and/or other chemicals which may have caused impairment within drivers of motor vehicles.  For postmortem sample analyses, a variety of evidence (e.g., blood, vitreous humor, urine) may be received.  These cases are usually limited to analyzing samples from decedents as a result of motor vehicle crashes, homicides, and traumatic suicides. 

A productive and collaborative relationship has emerged between the Office of The Chief Medical Examiner (OCME) and the DSS laboratory as a result of the DSS expanding its toxicological services to include post-mortem samples.  Analyses performed within the Toxicology Unit utilize gas chromatography and mass spectrometry methodologies, with reference to extensive chemical libraries for the identification of drugs and other chemicals.  Headspace gas chromatography, liquid chromatography/mass spectrometry, and accurate-mass determination are all powerful instrumental techniques that are housed and available to be used by toxicologists. This unit also provides conversions of ethanol data for law enforcement in situations where submitting agencies may only have hospital medical records indicating ethanol within suspected DUI operators. 

Controlled Substance/Breathalyzer Unit

The Breath-Alcohol sub-unit is responsible for training and certifying personnel as instructors, and subsequently operators, of the use of breath-alcohol testing devices utilized within the state of CT. This sub-unit instructs how to maintain statewide quality assurance and operational standards for use by all law enforcement agencies when administering breath-alcohol tests.  Evaluation and maintenance certification of breath-alcohol testing instruments used within the State of Connecticut is conducted and documents offering proof are maintained.  Examiners may be summoned to provide education certificates for instructors and/or maintenance records for instruments during either discovery or freedom of information act (FOIA) requests. 

Controlled Substance sub-unit personnel identify drugs, concentrating on substances that are controlled within the Controlled Substances Act. Bulk drugs, drug residue, and drug paraphernalia are readily seen as evidence that is submitted for analysis.  While the more commonly analyzed substances tend to be marijuana, cocaine, MDMA, and heroin, newer drugs such as synthetic cannabinoids, bath salts, and fentanyl have been increasing in frequency.  Pills and tablets, both manufactured and counterfeit also comprise the evidence received within that sub-unit.  Recent trends include the continually expanding set of new synthetic analogue drugs commonly referred to as synthetic marijuana/cannabinoids and bath salts. Typical instrumentation used by analysts in this field includes Fourier-transform infrared spectrophotometry (FTIR) and gas chromatography/mass spectrometry (GC/MS).  Occasionally, personnel respond with CT Department of Energy and Environmental Protection (DEEP), as well as the U.S. Drug Enforcement Administration (DEA), to clandestine drug labs in the field.  Analysts can provide both technical and safety support during the response, as well as answer questions that investigators might have regarding evidence collection and proper packaging.

Computer Crimes and Electronic Evidence Unit

The Computer Crimes and Electronic Evidence Unit is divided into two separate sub-units:  the Investigations Unit and the Forensic Analysis Unit.  In this Unit, State and local police officers work in conjunction with computer forensic science examiners.  The Computer Crimes and Electronic Evidence Unit was one of the founding members of the Internet Crimes Against Children Task Force Program (ICAC).  The ICAC program is a national network of 61 coordinated task forces representing over 2,000 federal, state, and local law enforcement and prosecutorial agencies.  Since 1999, the Connecticut ICAC Task Force has continued to work with other federal, state and local law enforcement agencies in responding to cyber enticement, child exploitation and child pornography cases. Presently, the Connecticut ICAC Task Force consists of 47 affiliate local law enforcement agencies.  As part of this Task Force, Connecticut is a recipient of ICAC funding from the United States Department of Justice.

The goal of the Computer Crimes Forensic Analysis Unit is to examine seized computers and other electronic storage devices (ESD) such as cell phones, tablets, iPods, and gaming devices, for evidentiary value.  A significant number of cases involve the exploitation of children in the areas of human trafficking and child pornography, but unit also assists in the investigation of sexual assaults, white collar crimes, homicides and drug trafficking.  The Computer Crimes Forensic Analysis Unit will examine computers for web searches and other electronic history, provide cell phone data dumps, all of which may aid in an investigation.  With the increase of skimmer devices being uncovered in gas pumps, the Unit may be able to extract data from the skimmer devices to determine the date that a device was placed inside a pump.  This data extracted from these devices may also include a list of victims which were potentially compromised. 

In 2013, the Computer Crimes and Electronic Evidence Unit, the Chemistry Unit, and members of the CSP Canine Training Unit, collaborated to train dogs with the ability to detect electronic storage devices.  Currently, the State of Connecticut has two such canines in use and they have successfully aided investigators in the recovery of hidden electronic storage media.  This project has gained national attention and is anticipated to develop further over the next few years as a full-fledged training program. 

Multimedia and Image Enhancement Unit

The Multimedia and Image Enhancement Unit was created in 2007 and achieved ASCLD/LAB accreditation in the fall of 2011.  This Unit accepts analog and digital video, audio and photographic evidence, providing duplications and enhancements as requested.  The majority of the cases submitted to this Unit are for driving under the influence related charges.  Other casework can arise from a variety of investigations including homicides, sexual assaults or child pornography.

The Multimedia and Image Enhancement Unit also assists law enforcement agencies with video retrievals from the crime scene or related locations as well as provides Redactions for the DESPP Legal Affairs Unit.  Additionally, the Multimedia and Image Enhancement Unit can perform video enhancements to assist in the identification of vehicles or persons of interest.  The Unit is also able to provide audio enhancements to audio files by decreasing background noise.

Latent Print Unit

The Latent Print Unit analyzes and compares latent prints to known prints of individuals in an effort to make identifications or exclusions.  Latent prints are impressions produced by the ridged skin, known as friction ridges, on human fingers, palms, and soles of the feet. This Unit examines a variety of physical evidence utilizing the latest physical and chemical print development techniques. This Unit examines submitted photographs and lifts employing enhancement filters to bring out the best possible detail from latent evidence.  Comparisons are conducted between the latent print and known impressions using the ACE-V (analysis, comparison, evaluation and verification) methodology.  The DSS searches the Automated Fingerprint Identification System (AFIS) and currently uses the FBI’s Next Generation Identification (NGI) system, which replaced the IAFIS (Integrated Automated Fingerprint Identification System).  The DSS Latent Print Unit also approves the personnel utilizing local AFIS systems in police departments. The Latent Print Unit is able to use the latent print system to search latent prints left at crime scenes or developed from submitted evidence against a centralized national fingerprint repository. Both the AFIS and NGI systems return a list of potential candidates with corresponding fingerprint images and other related information for comparison purposes. The Latent Print Unit also uploads all unidentified latent prints into an Unsolved Latent File (ULF) located in the NGI System. 

In May of 2013, the Latent Print Unit began a Latent Pre-screening Project that resulted in an 11% reduction of cases that would normally have been submitted for Latent Print examinations.  The investigating agency would submit a high resolution image of a latent print that has been developed at a scene for a determination if this print is of value for further analysis.  In some cases, the high resolution images are of such good quality that an NGI/AFIS entry can be made.  In 2014, this prescreening program resulted in hits being immediately reported in 17% of these cases.  Due to the success and positive feedback of this pre-screening process, the Latent Print Unit has now implemented electronic submission of evidence.

Questioned Document and Imprints Units

The Questioned Document Unit routinely examines evidence to determine the authenticity of a document or writing.  Comparison of rubber stamp impressions to signature/handwriting comparison can also be provided. The Questioned Document Unit also examines scratch-off lottery tickets prior to release into the Lottery System.  Specifically, the Unit exams the test lots of the lottery games for quality of its “scratch coating” to make sure that tampering or detection of numbers is not possible until the ticket is purchased. 

The Imprints Unit examines footwear and tire-tracks for characteristics that are unique or individualizing in nature.  These characteristics may be used to make comparisons to known exemplars submitted for analysis.  Known exemplars are tread or tire track patterns that are replicated from known objects.

The Imprints Unit utilizes a shoeprint database called SICAR (Shoeprint Image Capture and Retrieval).  This database is used to search for a footwear manufacturer by the physical characteristics of the shoe tread pattern. 

Firearms Unit

This Unit receives evidence consisting of various types and calibers of firearms, firearm components, ammunition, and ammunition components.  The ammunition-type evidence is examined for microscopic markings to identify the possible make and model of the firearm that the ammunition evidence may have been used in.  In addition, images taken of the cartridge casings submitted to DSS are entered into the National Integrated Ballistic Identification Network system (NIBIN), a database containing high resolution images of cartridge case evidence.  These digital images can be compared to other images submitted by other Laboratories or Police Departments to determine if the same firearm was used, resulting in a database “hit”. 

This Unit also examines evidence for tool mark comparisons; e.g. forcible burglaries and property damage investigations.  Toolmark evidence can be important in cases when an item submitted with unique markings may be able to link several serial type property crimes.