Forensic Laboratory Section

Introduction

Forensic Laboratory Section Logo

The Forensic Laboratory Section is organized into two separate branches of technical scientific expertise.  The Analytical Sciences Branch that houses the Forensic Biology Unit, the Questioned Documents Unit and the Drug Analysis Unit, and the Comparative Sciences Branch that houses the Latent Print Unit and the Firearms Analysis Unit.

Overall the entire Forensic Laboratory Section is Managed by a single Laboratory Director who has two assigned Deputy Directors.  The Deputy Directors are each assigned one of the scientific branches to manage.  Each unit within those branches has at least on unit supervisor and one technical leader.  Within some units the supervisor and technical leader may be the same person.

Directorship and Quality Assurance

Director Forensic Laboratory Section Rana DellaRocco, M.S., M.P.A., ABC-MB: Director of the Forensic Laboratory Section & Quality Assurance Manager

The Forensic Laboratory Section is overseen by Director Rana DellaRocco who is also the Quality Assurance Manager for the Forensic Science & Evidence Services Division as a whole.  The Director and Quality Assurance Manager as whole works to strengthen the Laboratory's work product by ensuring that the laboratory follows stringent accreditation and regulatory requirements that are placed upon it.  The laboratory employs techniques and strategies such as internal auditing, external assessments, proficiency testing, management reviews, corrective actions and risk assessment to continually improve laboratory operations.

The Quality Office which is overseen by the Quality Assurance Manager is responsible for ensuring the requirements of this forensic laboratory quality assurance program are established, implemented, followed, and maintained.

Analytical Sciences Branch

Deputy Director Analytical Sciences Branch Kenneth B. Jones, MS, ABC-MB, CFM-I: Deputy Director of the Analytical Sciences Branch

The Analytical Sciences Branch of the Forensic Laboratory Section utilizes a variety presumptive and confirmatory testing methods in combination with sophisticated instrumentation to analyze and identify various types of evidence.

Presumptive testing utilizes a variety of chemical reactions and instrumental techniques to provide indications of the presence of certain evidence types, e.g. blood, seminal fluid, opioid.  Confirmatory testing further identifies a specific substance or biological material or specific drug.  Our Forensic Scientists assists investigators by performing tests on collected evidence and providing impartial, scientifically based information about evidence recovered from a crime scene.

The Analytical Sciences Branch of the laboratory is comprised of the Drug Analysis Unit, the Forensic Biology Unit and the Questioned Documents Unit.  These units are primarily responsible for the analysis and identification of unknown substances, the development of DNA profiles, the processing of development latent prints, and the comparison of handwriting, tire track and footwear evidence.  Using a wide variety of instrumental techniques and technology, the analytical sciences branch provide answers to investigators that otherwise would remain unknown.

The Baltimore Police Department's Forensic Laboratory Section's Analytical Science Branch has achieved International Accreditation through the ANSI-National Accreditation Board to the ISO/IEC 17025 International Forensic Testing Requirements.  This Branch, specifically the DNA Section of the Forensic Biology Unit, has also received continual passing FBI QAS external assessments.

Analytical Sciences Branch Units

Drug Analysis Unit

Drug Analyst using an FTIR with an ATR Attachement

Using both presumptive and confirmatory testing methods, the Drug Analysis Unit conducts a variety of testing on unknown powders, liquids, plants, and pills in order to determine whether they are illicit controlled dangerous substances.  Drug Analysts utilize gas chromatography/mass spectrometry, UV, and Fourier-transform Infrared Spectroscopy instrumentation to confirm the identification of submitted substances.

The drugs most commonly tested and detected included cocaine, fentanyl, and heroin.  Marijuana is tested on an as needed per request basis.

The Drug Analysis Unit also collaborates with researchers and task forces, providing data analysis of testing results and performing validation services of new methods or techniques to assist in addressing the impacts of drug use and abuse from both a public safety and public health perspective.

Forensic Biology Unit - Screening

Analyst looking through a microscope

Forensic screening streamlines laboratory workflow using methods for both latent print processing and serological testing. This model uses a triage system to identify and utilize the best testing methods that will produce the most probative results from evidence.

Analysts identify and prepare biological samples for DNA analysis using methods such as alternative light sources, microscopic analysis, and biochemical testing.  This allows for the identification of biological material such as blood, semen, or skin cells, that may be processed for DNA and link individuals to a crime.

Latent print processing uses techniques such as vacuum metal deposition (VMD), cyanoacrylate fuming, chemical treatment, and powdering to identify and develop fingerprints that may be forwarded to the Latent Print Unit for analysis and comparison. 

Forensic Biology Unit - DNA

DNA Analyst pipetting

DNA Analysts isolate DNA from samples identified through serological screening, and develop DNA profiles from the samples for comparison.  DNA analysis is conducted using the most current Short Tandem Repeat (STR) testing technology.  Through the use of robotics systems and advanced data analysis software, analysts are able to interpret samples that scientifically link individuals to crimes.

The DNA Analysis unit of the Baltimore Police Department was also one of the first laboratories in the country to utilize probabilistic genotyping software to analyze and interpret complex DNA mixtures and DNA profiles, providing results for evidence types that previously would have yielded useful results.

As of 2019, the DNA section of the Forensic Biology Unit has achieved more than 3000 DNA candidate matches in the Combined DNA Index System (CODIS), the National FBI DNA Database.  These hits provide links previously unknown to investigators and assist in solving a variety of case types, including cold cases.

Questioned Documents Unit

The Questioned Documents Unit examines and compares various document types as well as shoe and tire print impressions.  The majority of QD work is handwriting comparisons.

The QD Unit employs various technologies including microscopy and the Electrostatic Detection Apparatus (ESDA).  The senior examiner in the Questioned Documents Unit has more than 40 years of experience and is one of only two examiners in the entire State of Maryland.

Comparative Sciences Branch

Deputy Director Comparative Sciences Ethan Conway: Deputy Director Comparative Sciences Branch

Comparative science is the scientific analysis of two components, items, or images to determine if they come from a common source or origin.  Whereas analytical forensic scientists form opinions based upon data obtained from chemical reactions, immunoassays and complex scientific instrumentation, comparative scientists visually examine ranges of evidence to form an opinion based upon their expertise, experience and education.

The Baltimore Police Department Forensic Laboratory Section's Comparative Science Branch currently consists of the Firearms Analysis Unit and the Latent Print Unit, although there are several other comparative forensic science disciplines.

The Comparative Sciences Branch received its International Accreditation from ANAB in ISO 17025 for Forensic Testing in the Disciplines of Firearms/Toolmarks and Friction Ridge (Latent Prints) the same time as the Analytical Sciences Branch.

Since comparative science disciplines typically involve some lab work such as serial number restoration on firearms, a career path in comparative science typically requires an undergraduate degree in biology, chemistry, forensic science, criminal justice, or a closely related hard (natural) science.

In addition, analysts must have an eye for detail since unlike in some other disciplines, the evidence is not always obvious and right in front of you.  Analysts spend much of their time searching known items, such as fingerprints or casings, and trying to determine if it was the source of the unknown item (latent prints or casings from a crime scene).

Comparative Sciences Branch Units

Firearms Analysis Unit

Firearms Analyst performing a test fire

Firearms identification is primarily the study of microscopic markings appearing on the surfaces of bullet specimens, cartridge cases, and shot shells to identify those components as having been fired by a specific firearm.

A Firearms Analyst identifies and examines bullets, bullet fragments, cartridge cases and firearms used in crimes.  Analysts may also test fire firearms, study gunshot residue and shot pattern testing, complete toolmark examinations, and restore serial numbers.

Firearms and Toolmark analysts must be proficient in the use of laboratory instrumentation to effectively analyst and compare evidence.  In our lab, after hiring, our Firearms Analysts undergo a vigorous, on-site training in order to be able to work independently.

The Unit uses NIBIN, another database run by the Bureau of Alcohol, Tobacco, Firearms and Explosives.  NIBIN stands for the National Integrated Ballistic Information Network and is used to store, and retrieve digital image of fired cartridge cases throughout the United States.  All cases that have cartridge cases or test fired cartridge cases from semi-automatic firearms are eligible for entry into NIBIN.  When a new cartridge case is entered into the system, it is automatically compared to all cases of similar caliber already in the database.  Once an analyst compares the candidates for potential links that NIBIN supplied, different incidents that may have been committed with the same firearm regardless of location and jurisdiction can be linked creating a "lead."  

In addition to being one of the most productive Firearms Analysis Units in the country, the Firearms Analysis Unit has also stayed at the forefront of the industry with its participation in various pilots and programs.  The Unit participated in the pilot program for BallisticSearch, was the first to participate in the ATF's NIBIN Van Program, and is a current participant in Shotspotter. 

Latent Print Unit

Fingerprints as viewed using an alternate light source

The word latent means present but not visible, but can be developed by powder, chemicals, light sources or a combination of all.  Latent prints are unique impressions created by the ridges in human skin from fingers, palms, and soles of the feet and left intentionally or by chance on objects at crime scenes.  Latent prints, sometimes referred to as "evidence prints" can place a perpetrator at the scene of a crime and can place victims with suspects (kidnapping victims in perpetrator's car for instance).

Crime Laboratory Technicians recover the prints by applying special lights, chemicals, or by using high-tech powders, to capture the impression.  They will likely also photograph the prints.

Latent Print Analysts will use their experience, extensive training, and a variety of scientific tools to analyze latent prints recovered from a crime scene and then compare them to known subjects.  If there is sufficient quality and quantity of detail in agreement between the latent print and the known print, the analyst can conclude that two friction ridge impressions originated from the same source (i.e. an identification).  If the two impressions are not in agreement or the analyst cannot make a determination one way or the other, conclusions of exclusion or inconclusive can be reached.

Latent prints that are not identified to suspects, may be searched in the Automated Fingerprint Identification System (AFIS).  AFIS is the generic term for various local, state, and federal databases that store millions of known fingerprint records.  Latent prints are entered into the system, details in the latent are marked by the analyst, and the computer then compares the marked latent against all of the records in the database.  Within minutes, a list of possible candidates is returned to the analyst to compare against the questioned latent print.

Today, the Latent Print Unit is one of the most productive units in the United States.  They continue to evolve their policies and procedures to maintain efficiency while meeting the increased documentation standards of the forensic community.