Inside the Crime Lab: A Complete Tour of the Denver Police Crime Laboratory

Summary

The Denver Police Crime Lab offers a behind-the-scenes look at forensic science, showcasing units like Firearms and Tool Mark, Forensic Imaging, Latent Prints, Trace Evidence, Forensic Biology and DNA, and Crime Scene. Each unit utilizes advanced techniques and technology to analyze evidence, from fingerprinting and DNA profiling to ballistics and chemical analysis, playing a crucial role in solving crimes and ensuring justice.

Takeaways

• 🔎 The Denver Police Crime Lab is equipped with advanced tools and technologies to aid in forensic investigations.
• 👁️‍🗨️ Fingerprint identification is a crucial method for personal identification and is considered a strong link in the chain of evidence.
• 🔬 The lab uses various scientific instruments such as emission spectrographs and mass spectrographs to analyze evidence.
• 🚫 Clean spaces within the lab are maintained to prevent contamination, requiring personnel to wear masks, gloves, and lab coats.
• 🔍 Physical evidence is meticulously documented through photography and laboratory examination to ensure its integrity.
• 🔒 The Firearms and Tool Mark Unit conducts examinations to determine if specific tools or firearms were used in crimes.
• 📸 The Forensic Imaging Unit specializes in video analysis and photographic documentation of evidence for legal matters.
• 👁️‍🗨️ Latent prints are developed using techniques like cyanoacrylate fuming and compared to known prints for identification.
• 🧬 The Forensic Biology and DNA Unit processes biological evidence and develops DNA profiles for comparison with known samples.
• 🚔 The Crime Scene Unit responds to and processes crime scenes, employing various techniques to collect and preserve evidence.
• 🧪 The Forensic Chemistry Unit handles narcotics cases, blood alcohol analysis, and arson investigations, using instruments like gas chromatographs.

Q & A

What is the primary role of the Denver Police Crime Lab?

The primary role of the Denver Police Crime Lab is to conduct forensic investigations that support criminal cases, process evidence, and contribute to the identification and apprehension of criminals.

How does the fingerprint unit at the crime lab develop latent prints?

The fingerprint unit uses a cyanoacrylate fuming chamber, also known as a superglue chamber, to develop latent prints. The superglue vapor adheres to the print residue, and a liquid dye stain is applied to make the prints visible under a laser.

What is the purpose of the firearms and tool mark unit in the crime lab?

The firearms and tool mark unit examines firearms for proper functionality, performs test firings, conducts gunpowder pattern testing to determine distances, and compares fired bullets and cartridge cases to specific firearms. It also restores obscured serial numbers and uses the national integrated ballistic information network (NIBIN) for comparisons.

What does the forensic imaging unit do at the crime lab?

The forensic imaging unit retrieves video from crime scenes, captures still images of suspects and vehicles, assists with video playback and review, and securely archives photographs of evidence. They also convert older analog media to digital formats for easier analysis.

How does the trace evidence unit contribute to crime investigations?

The trace evidence unit collects and analyzes microscopic debris, such as hair, fibers, glass, and paint particles, to establish elements of a crime. They use tools like comparison microscopes and chemical analysis instruments to identify and compare evidence.

What is the significance of the forensic biology and DNA unit in the crime lab?

The forensic biology and DNA unit examines evidence for biological matter, identifies biological fluids, and processes samples for DNA analysis. They develop DNA profiles from items of evidence and compare them to known DNA profiles to help solve cases.

What are some of the specialized techniques used by the crime scene unit?

The crime scene unit uses specialized techniques such as shooting reconstruction, bullet trajectory analysis, blood stain pattern analysis, DNA and trace evidence collection, and latent fingerprint processing.

What is the role of the forensic chemistry unit in the crime lab?

The forensic chemistry unit handles narcotics cases, blood alcohol analysis for DUI investigations, and ignitable liquid analysis for arson cases. They use instruments like gas chromatographs and mass spectrometers for substance identification and quantification.

Why is the ISO 17025 accreditation important for the Denver Police Crime Lab?

ISO 17025 accreditation is important because it is an international standard that ensures the lab's testing and calibration services are reliable and accurate. Achieving this accreditation demonstrates the lab's commitment to quality and compliance with rigorous standards.

How does the quality assurance unit support the crime lab's operations?

The quality assurance unit maintains documentation, ensures compliance with ISO standards, processes laboratory requests, manages case reports, orders supplies, processes subpoenas, and provides case discovery for trials, thereby supporting the overall quality and efficiency of the crime lab.

Outlines

00:00

🔎 Introduction to Forensic Science

The script opens with an enthusiastic introduction to the fun and fascinating world of forensic science, emphasizing its role in personal identification and evidence collection. It discusses the replacement of traditional guest work with modern scientific methods, highlighting the importance of preserving evidence for laboratory examination. The script introduces various scientific tools like emission spectrographs and mass spectrographs, and mentions the use of microscopes to compare evidence such as bullets. The Denver police crime lab is introduced, with Greg Lear, the director, explaining the lab's commitment to forensic investigations and community service. The video aims to provide insight into the workings of a forensic lab and inspire potential forensic scientists.

05:01

🔍 Firearm and Tool Mark Examination

This section delves into the operations of the Firearms and Tool Mark unit, detailing their examinations of firearms for functionality and evidence comparison. It includes test firing, gunpowder pattern testing, and microscopic comparison of bullets and cartridge cases. The unit also restores obscured serial numbers and uses the National Integrated Ballistic Information Network (NIBIN) to match evidence to previous incidents. The script mentions the use of a Leica comparison microscope for detailed examinations and the maintenance of a firearm reference collection for training and research.

10:01

📸 Forensic Imaging Techniques

The Forensic Imaging unit is highlighted for its role in video analysis and evidence retrieval from crime scenes. The unit captures still images of suspects and vehicles, assists with video playback, and uses sophisticated editing systems for complex cases. They also archive photographs of evidence and assist in cold case investigations by digitizing older media formats. The unit's responsibilities include photographing DPD personnel, victims, suspects, and property items for evidence purposes.

15:02

👁‍🗨 Latent Print and Trace Evidence Analysis

The Latent Prints unit's focus on developing and comparing latent prints to known records is discussed. They use tools like cyanoacrylate fuming chambers and databases to identify potential matches. The Trace Evidence unit's role in analyzing microscopic debris, such as hair, glass, and paint particles, is also covered. They use scanning electron microscopes and comparison microscopes to compare evidence with known samples. The unit also employs chemical analysis instruments like ion chromatographs to identify substances from debris.

20:05

🧬 Forensic Biology and DNA Analysis

The Forensic Biology and DNA unit's work on examining evidence for biological matter and developing DNA profiles is described. They handle a wide range of cases, including homicides, sexual assaults, and property crimes. The process involves visual examination, sample collection, DNA extraction, quantitation, amplification, and detection. The unit uses alternative light sources to locate invisible stains and stores biological evidence in a walk-in freezer. They also utilize the Combined DNA Index System (CODIS) to match evidence to known profiles and solve cases.

25:06

🚔 Crime Scene Processing and Forensic Chemistry

The Crime Scene unit's responsibilities in managing and documenting crime scenes, collecting evidence, and employing various processing techniques are outlined. The unit has transitioned from sworn officers to civilian personnel. The Forensic Chemistry unit's work in narcotics analysis, blood alcohol testing, and arson investigations is also detailed. They use instruments like gas chromatographs and mass spectrometers for substance analysis and have achieved ISO 17025 accreditation, indicating compliance with international standards for testing and calibration services.

🏛️ Quality Assurance and Accreditation

The script concludes with a focus on the Forensic Quality Assurance unit's role in maintaining documentation, ensuring compliance with ISO standards, and supporting laboratory operations. The Denver Police Crime Laboratory's accreditation under ISO 17025 is emphasized, showcasing the lab's commitment to quality and reliability in forensic analysis. The journey to achieve accreditation for each unit within the lab is briefly recounted, highlighting the lab's dedication to excellence in forensic science.

Keywords

💡Forensic Science

Forensic science is the application of scientific principles and techniques to the investigation of crime. It plays a crucial role in the video's theme by showcasing how various units within the Denver police crime lab use forensic science to analyze evidence and aid in criminal investigations. For example, the video discusses how fingerprints, tool marks, and DNA are analyzed to link suspects to crime scenes.

💡Latent Fingerprints

Latent fingerprints are invisible to the naked eye and are made by the natural oils and sweat on a person's fingertips. The video explains how the latent prints unit uses a cyanoacrylate fuming chamber to develop these prints, which are then compared to known prints to identify individuals. This process is vital for personal identification and forms a key part of the evidence chain in criminal cases.

💡Firearms and Tool Mark Unit

This unit is responsible for examining firearms and tools for unique marks that can link them to specific crimes. The video mentions how this unit conducts mechanical function checks on firearms, test fires them for bullet and cartridge case specimens, and uses the national integrated ballistic information network (NIBIN) to compare marks on fired cartridge cases to a database of previous incidents.

💡Forensic Imaging

Forensic imaging involves the use of photography and video analysis to document and enhance evidence. The video describes how the forensic imaging unit retrieves video from crime scenes, captures still images of suspects, and uses video editing systems to enhance images for clearer identification. This is essential for providing visual evidence that can be used in court.

💡Trace Evidence

Trace evidence refers to small, often microscopic, pieces of material that can be found at crime scenes. The video explains how the trace evidence unit collects and analyzes this debris, such as hair, fibers, and paint particles, to help establish the elements of a crime. The use of a scanning electron microscope to magnify items up to 300,000 times is highlighted, demonstrating the unit's advanced techniques.

💡DNA Analysis

DNA analysis is a method of identifying individuals through the examination of their genetic material. The video details how the forensic biology and DNA unit develops DNA profiles from evidence and compares them to known profiles. The process includes DNA extraction, quantitation, amplification, and detection, culminating in the creation of a DNA profile that can be matched to suspects or victims.

💡Crime Scene Unit

The crime scene unit is tasked with the response to and processing of crime scenes. The video outlines how this unit manages crime scenes, documents evidence through photography and video, and collects and preserves physical evidence. The unit's work is critical for the initial collection of evidence that will be analyzed by other forensic units.

💡Forensic Chemistry

Forensic chemistry involves the analysis of chemical substances related to crime, such as narcotics, explosives, and bodily fluids. The video describes how the forensic chemistry unit handles narcotics cases, blood alcohol cases, and arson investigations. The unit uses instruments like gas chromatographs and mass spectrometers to identify and analyze substances, contributing to the resolution of cases.

💡Quality Assurance

Quality assurance in a forensic context ensures that the laboratory's procedures and analyses meet established standards. The video mentions that the Denver police crime laboratory is accredited under ISO 17025, an international standard for testing and calibration services. This accreditation signifies that the lab maintains rigorous documentation and a quality system to monitor all forensic analyses.

💡National Integrated Ballistic Information Network (NIBIN)

NIBIN is a database used by law enforcement agencies to compare markings on fired cartridge cases. The video explains how the firearms and tool mark unit uses NIBIN to capture digital images and 3D renderings of unique marks, which are then compared to the database to identify potential matches with previous shooting incidents.

💡Cold Case Investigations

Cold cases are unsolved crimes that have gone cold due to lack of evidence or leads. The video mentions that the forensic imaging unit assists in cold case investigations by converting older analog media to digital formats, making them easier to analyze. This process can potentially uncover new evidence or leads that were not apparent at the time of the original investigation.

Highlights

Science plays a crucial role in criminal investigations, providing fascinating insights and methods.

Fingerprints are a key form of evidence, offering a positive means of personal identification.

Old-fashioned guesswork has been replaced by scientific techniques that save time and improve accuracy.

The Denver police crime lab is equipped with advanced tools like emission and mass spectrographs for evidence analysis.

Physical evidence is photographed and preserved for laboratory examination to maintain its integrity.

Dual microscopes are used to compare evidence, such as bullets, for identical markings.

The lab's clean spaces and protocols ensure that evidence remains uncontaminated.

The firearms and Tool Mark unit conducts various examinations, including mechanical function checks on firearms.

Gunpowder pattern testing helps determine the distance a firearm was from a victim.

The national integrated ballistic Information Network (NIBIN) is used to compare marks on cartridge cases.

Forensic Imaging retrieves and analyzes video evidence from crime scenes.

The latent prints unit uses a cyanoacrylate fuming chamber to develop latent prints on evidence.

Trace evidence unit analyzes microscopic debris to help establish the elements of a crime.

Forensic biology and DNA unit examines evidence for biological matter and develops DNA profiles.

The crime scene unit responds to and processes approximately 5,000 crime scenes each year.

The forensic chemistry unit handles narcotics cases and blood alcohol analysis.

The Denver police crime laboratory is accredited under ISO 17025, an international standard for testing and calibration services.

Transcripts

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science is fun it helps you to learn and

oh what fun it would

be fascinating interesting mysterious

wonderful this only the

beginning okay beans you all set to fire

it up fire it

up

this is called latent

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fingerprints fingerprints provide a

positive means of personal

identification and form an indisputable

Link in the chain of

evidence it is our responsibility to

identify stains that are made by the

various body

fluids old fashioned guest work is

replaced by it saving ours in following

useless

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clu to the scientist

scien the facilities we have available

for this purpose include the emission

spectrograph the mass

spectrograph fibers attached to the

window casing these pieces of evidence

are preserved for laboratory

examination check this

out

when physical evidence is found it is

immediately

photographed these pieces of evidence

are preserved for laboratory examination

Che

out here our dual microscopes being used

to see if two bullets are of identical

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make it's where

science they may prove innocence as well

as guilt

welcome to the Denver police crime lab

I'm Greg Lear director of the laboratory

this facility was developed with clean

spaces which are areas inside each crime

lab unit that must remain free of any

contamination masks gloves and lab coats

are required inside many of these clean

rooms which is why we can't give you a

closer look behind the scenes of the lab

instead we've produced this video to

give you an intimate look at what goes

into a forensic investigation you'll

learn about each unit of the crime lab

and how their results can impact the

outcome of criminal cases be sure to ask

your tour guide any questions you might

have especially if you're interested in

becoming a forensic scientist or a crime

scene investigator someday they are

unique professions and a great way to

serve the public and contribute to your

community we believe the Denver police

crime laboratory and our Personnel are

the best in the United States if not the

world and we strive to make Denver a

better place to to live and work every

single day you can find more information

about the Denver Police Department and

all the important work they do by

following them

online we hope you enjoy your time at

the crime lab and Come Away with a

better understanding of how forensic

investigations really

work the firearms and Tool Mark unit

conducts many different types of

examinations they do mechanical function

checks on Firearms to see if they're

working

properly this includes test firing of

firearms for

bullet and cartridge Cas

specimens for possible comparison with

evidence gunpowder pattern testing also

known as proximity testing to determine

the distance a firearm was from a

victim microscopic comparison of fired

bullets and cartridge cases to determine

if they were fired by a specific

firearm microscopic comparison of tools

like

screwdrivers wire cutters or punches to

Tool marks or physical matches left at a

crime

scene and restoration of obscured serial

numbers on firearms and other objects

using specialized

assets the firearms and Tool Mark unit

also utilizes the national integrated

ballistic Information Network or nbin

database entries and examinations nin

captures digital images and 3D

renderings of unique marks on fired

cartridge cases recovered from crime

scenes or test fired on our forensic

Firearms range it Compares these images

to others in the niban database to see

if they match any previous shooting

incidents any potential associations

found using the database are confirmed

via traditional microscopic comparisons

this is done using our Leica comparison

microscope which is the primary

instrument used by a firearm and Tool

Mark

examiner this microscope allows for the

side-by-side comparison of evidence at

up to 60 times

magnification the firearms and Tool Mark

unit maintains a large firearm reference

collection which serves an important

role in training and

research it provides a reference for

serial number appearance composition and

location and is a source for replacement

parts when they're needed to make

damaged or disassembled evidence

Firearms

operable the final stop on our tour of

the firearms and Tool Mark unit is the

forensic Firearms range this 75- ft long

space is used to safely test Firearms

when no bullet recovery is

necessary when a test bullet is needed

the bullet recovery tank is

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used this specialized water tank allows

for the collection of fired bullets that

maintain their original undamaged

condition

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the forensic Imaging unit consists of

personnel trained in forensic Imaging

techniques in video analysis using

scientific examination comparison and

evaluation of evidence in legal

matters the forensic Imaging unit's

primary function is retrieving video

from crime scenes to capture still

images of

suspects

vehicles and Persons of Interest for

investigators this unit also assists

detectives with playback and review of

acquired surveillance

video with video coming from many

different sources playback of

proprietary video can be quite complex

the images cannot be distorted or appear

altered in any way from their original

appearance of on the digital video

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recorder a sophisticated video editing

system is used to work on more complex

cases this software allows an analyst to

enhance a video image and make it easier

to view unique identifying

characteristics edited video will

sometimes be released to the public in

an attempt to locate suspects or Persons

of

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Interest the forensic Imaging unit is

also responsible for securely archiving

photographs of evidence from crime

scenes traffic investigations and other

crime lab units these images are sent to

a secure server then retrieved as needed

for detective case filings or

trial the unit photographs dpd personnel

as well as victims suspects and property

items for use as evidence and performs

other specialized photography as needed

by investigators they help train other

units to photograph evid

and also train sexual assault nurse

examiners throughout the city of

Denver finally the forensic Imaging unit

helps assist in Cold Case investigations

and prosecution this is done by

converting older analog media like VHS

tapes and audio cassettes to a cleaner

easier to navigate digital

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format

the main responsibility of the latent

prints unit is to process evidence for

the presence of latent prints then

compare them to known fingerprints and

palm

prints one of our main tools to develop

latent prints is the cyanoacrylate

fuming chamber also known as a superglue

chamber a small tray of superglue is

heated until it becomes a

vapor humidity is added to the chamber

causing the Vapor to adhere to any

latent print residue an individual may

have left

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behind a liquid die stain is then

applied to the items the stain adheres

to the cyanoacrylate residue making any

latent prints easier to view under a

laser the die stain on these items is

activated when put under the

laser wearing color filtered goggles an

examiner can visualize any possible

latent prints that may not be visible to

the naked

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eye when we have Laten prints to examine

and compare to known prints we have

access to two searchable databases one

is a federal database that searches

criminal civil and military print

records the other is a state database

that searches criminal and civil print

records

both databases assist us in identifying

latent prints by returning a list of

possible matches based on the unique

characteristics of each print an

examiner reviews this list to check for

any potential

matches if an identification appears

likely the examiner then completes a

manual comparison of the latent print to

the known print from the

database while there are many tools to

assist the latent prints unit in

identifying print matches this final

manual comparison is always completed by

an expertly trained Laten print

examiner almost 100 years ago Professor

Edmund lart stated for the microscopic

debris that covers our clothes and

bodies are the mute Witnesses sure and

faithful to all of our movements and all

of our encounters the trace evidence

unit is responsible for collecting and

analyzing that microscopic debris to

help establish the elements of a

crime analysis can be performed on the

smallest of items a single hair found on

a weapon used in an

assault glass discovered on the clothing

of a burglary suspect and even

microscopic particles of paint found on

the victim of a hit and

run

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this kind of test is performed on a

scanning electron microscope which can

magnify items up to 300,000 times their

normal

size that's enough to detect microscopic

particles of explosive primer on a

suspect's hands or

clothing a common tool used by analysts

in this unit is the comparison

microscope a comparison microscope is

essentially two compound microscopes

tied together with an optical Bridge so

that details of known samples can be

compared side by side with samples of

potential

evidence other microscopes utilized in

the microscopy laboratory include a

polarizing

microscope fluorescence

microscope and phase contrast

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microscope the scientists in the trace

evidence unit also utilize modern

chemical analysis instruments in their

evaluations an ion chromatograph for

example is routinely used to identify

chemical ions contained in debris from

explosives

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investigations the forensic biology and

DNA unit occupies the entire second

floor of the Denver police crime

laboratory the forensic biology unit

examines EV evidence recovered from

crime scenes for potential biological

matter they identify biological fluids

then take swabs or cuttings from the

evidence and process them for

analysis cases that test positive in the

forensic biology unit go on to forensic

DNA analysis the goal of the DNA unit is

to develop DNA profiles from items of

evidence and compare them to known DNA

profiles from crime

investigations

evidence is examined from many types of

cases including homicides sexual

assaults robberies aggravated assaults

kidnapping and property crimes like

burglaries and theft from a motor

vehicle cold cases are also examined

including homicides and sexual assaults

dating back to the

1960s work in the forensic biology unit

begins with a visual examination of

evidence for staining

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biologists take samples of potential

stains to test for the presence of blood

semen saliva or cellular

material hairs can also be tested if

they contain Roots suitable for DNA

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analysis stains not visible to the naked

eye can be located with an alternative

light source some body fluids fluores

under this blue light making it a useful

tool for finding stain stains that

aren't visible using natural

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light any biological evidence obtained

is stored in a walk-in freezer until

it's ready for DNA

analysis the DNA analysis process uses a

variety of manual and cuttingedge

robotic methods to analyze samples and

develop DNA

profiles every DNA sample goes through a

four-step process the first is a DNA

extraction which is done to purify the

DNA in a

sample after extraction samples are

passed through a secure Chamber from the

pre-amplification to the

postamplification

laboratory the next step is DNA

quantitation which determines how much

DNA is present in each

sample that's followed by an

amplification step where the DNA is

copied millions of

times finally the DNA is detected on an

instrument called a genetic

analyzer this machine assembles the

finished DNA profile which analysts use

to determine if biologic evidence from a

crime scene matches the known DNA

profile of a victim or

suspect DNA cases that are submitted

without a known suspect can be searched

in the combin bined DNA index system or

codus database this is the largest DNA

catalog in the world with over 14

million profiles codus is used by law

enforcement agencies in the United

States to help solve unsolved

cases the primary responsibility of the

crime scene unit is to assist detectives

with a response to and processing of

approximately 5,000 crime scenes each

year crime scenes include everything

from burglaries auto theft and

aggravated assaults to more complex

scenes like homicides sex assaults and

officer involved

shootings processing crime scenes

involves crime scene

management documentation including

photography and

video and the identification collection

and preservation of

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evidence depending on the type of crime

scene several different specialized

processing techniques can be used these

include shooting reconstruction and

bullet

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trajectory blood stain pattern

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analysis DNA and trace evidence

collection

and Laten fingerprint

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processing the crime scene unit utilizes

a 35- fot mobile crime scene Command

Center at Major scenes to help

facilitate staging and

processing in the forensic garage at the

Denver police crime lab there are three

separate vehicle processing Bays one of

the Bays features a hydraulic lift used

to search for evidence on the underside

of

vehicles another Bay is equipped with a

cyanoacrylate or superglue fuming

chamber this allows investigators to

fume an entire vehicle at once then

locate recover and submit latent

fingerprints for

analysis a full complement of pneumatic

tools is also available in the forensic

garage these are used to disassemble

vehicles and recover

evidence

in 2013 the crime scene unit began a

change from sworn police officers to

civilian Personnel today the entire unit

is staffed by

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civilians the forensic chemistry unit

handles over 5,000 narcotics cases per

year which requires the analysis of 10

tens of thousands of

items the unit processes over 800 blood

alcohol cases each year used to

determine if a DUI has been

committed the forensic chemistry unit

also performs an analysis for ignitable

liquids and arson investigations to

assist the Denver police and fire

departments as part of its

state-of-the-art laboratory the forensic

chemistry unit has gas generators to

produce all the gases used by its

instruments

the generators produce hydrogen as a

carrier gas and fuel gas nitrogen as a

carrier gas and Ultra purified zero air

used in flame ionization detectors and

to purge water from some

instrumentation here vials of blood are

being prepared for heads space analysis

used in suspected DUI

cases alcohol in the blood samples is

analyzed by heating the blood to for

Force the volatile alcohol into the air

at the top of the

vial to start the process samples are

placed into a heated head space Auto

sampler this machine takes the vials and

places them into an

oven when they reach the proper

temperature a sample is collected from

the head space and injected into an

instrument called a gas

chromatograph the alcohol value of the

blood sample can then be determined

a common instrument used to analyze

controlled substances is the forer

transform infrared spectr

photometer it takes approximately 30

seconds to perform this analysis which

produces a structural identification of

relatively pure organic

compounds controlled substances are

verified using a series of color tests

to indicate the possible presence of

different

narcotics

the orange color here indicates the

sample contains an amphetamine like

compound possibly

methamphetamine the next sample remains

pink after testing indicating it does

not contain

cocaine and the third sample turns a

dark blue color which means there is a

secondary amine

present the result of these three tests

show the sample is likely

methamphetamine in addition to narcotics

testing the forensic chemistry unit also

analyzes for ignitable liquid in Arsen

debris

cases the sample being prepared here

will be heated in an oven along with a

carbon

tab the small tab which is placed on the

lid of the testing container will absorb

any volatile compounds that are driven

off the material

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inside those compounds are then

extracted from the carbon tab using a

solvent

they can be analyzed using an instrument

called a gas chromatograph Mass

spectrometer which is also used in

controlled substance

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analysis the forensic quality assurance

unit provides administrative support to

Crime Scene Personnel forensic

scientists and and laboratory management

quality assurance Personnel are

responsible for maintaining all

documentation and demonstrating

compliance with ISO standards in the

quality

program other responsibilities include

processing laboratory

requests

pagination filing of case

reports ordering laboratory

supplies processing

subpoenas and providing case Discovery

for trial

the Denver police crime laboratory is

accredited under ISO

17025 this is an international standard

that governs testing and calibration

Services it requires extensive

documentation and a quality system be in

place to monitor all activities and

forensic analysis completed within the

laboratory it took more than 7 years for

the crime lab to achieve ISO 17025

accreditation for every unit forensic bi

biology DNA was the first unit to

receive accreditation in 2005 they were

followed by forensic chemistry and trace

evidence in 2006 in 2009 the Firearms

tool Mark and Laton Prince units

completed accreditation and in 2011 the

forensic Imaging and crime scene units

received their accreditation making the

entire Denver police crime laboratory

ISO

17025

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accredited

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