Forensic Science

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<div class="nist-block nist-block--no-margin"> <div class="entity-reference"> <img loading="lazy" src="/web/20240226171941im_/https://www.nist.gov/sites/default/files/images/2021/08/25/fingerprint.jpg" width="1200" height="248" alt="blue background with partial bright blue fingerprint overtop" typeof="foaf:Image"/> </div> </div> </div> <div class="nist-section-header__main grid-container"> <div class="grid-row"> <div class="nist-section-header__title"> <h1 class="nist-page__title">Forensic Science</h1> </div> </div> </div> </div> </div> <div class="grid-container"> <div class="nist-page__region nist-page__region--topic-description padding-top-4 margin-top-1"> <div class="nist-region-heading"> <h2>Overview</h2> </div> <div class="grid-row"> <div class="tablet:grid-col-8 padding-right-5 margin-bottom-4"> <div class="text-with-summary"> <p>NIST is working to strengthen forensic practice through research and improved standards. Our efforts involve three key components:</p> <h2>Science</h2> <p>We conduct <a href="https://web.archive.org/web/20240226171941/https://www.nist.gov/topics/forensic-science/research">scientific research</a> in several forensic disciplines, including DNA, ballistics, fingerprint analysis, trace evidence, and digital, among others. We provide physical reference standards and data that help forensic laboratories validate their analytical methods and ensure accurate test results.</p> <p>We also support CSAFE, a NIST Center of Excellence in Forensic Science, which is working to develop new statistical methods for use in evidence examination</p> <div class="grid-row grid-gap"> <div class="grid-col-9"> <h2>Policy</h2> </div> </div> <p>We co-chaired, with the Department of Justice, the <a href="https://web.archive.org/web/20240226171941/https://www.nist.gov/topics/forensic-science/national-commission-forensic-science">National Commission on Forensic Science</a>, which formulated recommendations for the U.S. Attorney General on matters such as accreditation requirements for forensic science service providers.</p> <h2>Practice</h2> <p>We administer the <a href="https://web.archive.org/web/20240226171941/https://www.nist.gov/topics/forensic-science/organization-scientific-area-committees-osac">Organization of Scientific Area Committees for Forensic Science </a>(OSAC), which is facilitating the development of science-based standards and guidelines for a broad array of forensic disciplines.</p> </div> </div> <div class="tablet:grid-col-4"> <div class="nist-block nist-block--no-margin"> <h2 class="nist-block__title">Featured Content</h2> <div class="nist-field nist-field--label-hidden nist-field--link-list link font-sans-sm"> <div class="nist-field__items"> <div class="nist-field__item"><a href="/web/20240226171941/https://www.nist.gov/spo/forensic-science-program">Forensic Science Program</a></div> <div class="nist-field__item"><a href="/web/20240226171941/https://www.nist.gov/topics/forensic-science/reference-materials-standards-and-guidelines">Reference Materials, Standards, and Guidelines</a></div> <div class="nist-field__item"><a href="/web/20240226171941/https://www.nist.gov/osac">Organization of Scientific Area Committees for Forensic Science</a></div> <div class="nist-field__item"><a href="/web/20240226171941/https://www.nist.gov/forensic-science/interdisciplinary-topics/scientific-foundation-reviews">Scientific Foundation Reviews</a></div> <div class="nist-field__item"><a href="/web/20240226171941/https://www.nist.gov/feature-stories/dna-mixtures-forensic-science-explainer">DNA Mixtures: A Forensic Science Explainer</a></div> <div class="nist-field__item"><a href="/web/20240226171941/https://www.nist.gov/feature-stories/safe-efficient-reliable-new-science-fight-against-killer-drugs">Safe, Efficient, Reliable: New Science in the Fight Against Killer Drugs</a></div> </div> </div> </div> </div> </div> </div> </div> <div class="bg-base-lightest padding-y-5 margin-y-4"> <div class="nist-page__region nist-page__region--topic-list grid-container"> <div class="views-element-container nist-block margin-bottom-0"> <div><div class="js-view-dom-id-dba436022d7a9a7fe04cd28b54b50d1769aa0c7de47aba74e8bb2ee979b85fc2"> <div class="nist-block margin-bottom-0"> <div class="nist-region-heading"> <h2>Forensic Science Topics</h2> </div> <ul class="add-list-reset link-list"> <div class="grid-row"> <div class="tablet:grid-col-6"> <li class="font-sans-md padding-bottom-205"><div class="views-field views-field-field-shared-section"><div class="field-content nist-icon nist-icon--before nist-icon--arrow-right2"><a href="/web/20240226171941/https://www.nist.gov/digital-evidence" hreflang="en">Digital evidence</a></div></div></li> </div> <div class="tablet:grid-col-6"> <li class="font-sans-md padding-bottom-205"><div class="views-field views-field-field-shared-section"><div class="field-content nist-icon nist-icon--before nist-icon--arrow-right2"><a href="/web/20240226171941/https://www.nist.gov/drugs-toxicology" hreflang="en">Drugs & toxicology</a></div></div></li> </div> <div class="tablet:grid-col-6"> <li class="font-sans-md padding-bottom-205"><div class="views-field views-field-field-shared-section"><div class="field-content nist-icon nist-icon--before nist-icon--arrow-right2"><a href="/web/20240226171941/https://www.nist.gov/firearms-and-toolmarks" hreflang="en">Firearms and toolmarks</a></div></div></li> </div> <div class="tablet:grid-col-6"> <li class="font-sans-md padding-bottom-205"><div class="views-field views-field-field-shared-section"><div class="field-content nist-icon nist-icon--before nist-icon--arrow-right2"><a href="/web/20240226171941/https://www.nist.gov/forensic-biometrics" hreflang="en">Forensic biometrics</a></div></div></li> </div> <div class="tablet:grid-col-6"> <li class="font-sans-md padding-bottom-205"><div class="views-field views-field-field-shared-section"><div class="field-content nist-icon nist-icon--before nist-icon--arrow-right2"><a href="/web/20240226171941/https://www.nist.gov/forensic-genetics" hreflang="en">Forensic genetics</a></div></div></li> </div> <div class="tablet:grid-col-6"> <li class="font-sans-md padding-bottom-205"><div class="views-field views-field-field-shared-section"><div class="field-content nist-icon nist-icon--before nist-icon--arrow-right2"><a href="/web/20240226171941/https://www.nist.gov/trace-evidence" hreflang="en">Trace evidence</a></div></div></li> </div> </div> </ul> </div> </div> </div> </div> </div> </div> <div class="nist-page__region nist-page__region--main"> <div class="nist-block"> <div class="grid-container margin-y-5"> <div class="paragraph paragraph--type--topic-text paragraph--view-mode--default"> <div class="nist-region-heading"> <h2> What Is Forensic Science? </h2> </div> <div class="tablet-lg:grid-col-8 padding-right-5"> <div class="text-long"><p>Forensic science is the use of scientific methods or expertise to investigate crimes or examine evidence that might be presented in a court of law. Forensic science comprises a diverse array of disciplines, from fingerprint and DNA analysis to anthropology and wildlife forensics. Though they represent varied disciplines, all forensic scientists face a common set of challenges. How do you ensure that forensic methods produce reliable results? How do you communicate findings to a jury or other nonexperts in a way that is accurate and understandable? How do you keep up with new technology without falling behind on casework? Meeting these and other challenges is critical to ensuring that forensic science remains a powerful force in support of justice and public safety.</p></div> </div> </div> </div> <div class="grid-container margin-y-5"> <div class="paragraph paragraph--type--topic-text paragraph--view-mode--default"> <div class="nist-region-heading"> <h2> Key Accomplishments </h2> </div> <div class="tablet-lg:grid-col-8 padding-right-5"> <div class="text-long"><ul><li><strong>Forensic SRMs:</strong> NIST develops standard reference materials (SRMs) for forensic science, including <a data-entity-substitution="canonical" data-entity-type="node" data-entity-uuid="3b92c00d-6859-4643-9729-94473b10d7a2" href="/web/20240226171941/https://www.nist.gov/news-events/news/2018/09/nist-updates-forensic-standard-reference-materials" title="NIST Updates Forensic Standard Reference Materials">the Standard Bullet and the Human DNA Quantitation Standard</a>. By helping to ensure that forensic labs produce accurate measurements when analyzing crime scene evidence, these SRMs contribute to public safety and fairness in the criminal justice system.</li> <li><strong>Digital forensics:</strong> NIST’s <a data-entity-substitution="canonical" data-entity-type="node" data-entity-uuid="581a735d-233b-4fe3-906b-cc8bcd6f11e2" href="/web/20240226171941/https://www.nist.gov/news-events/news/2018/09/database-software-fingerprints-expands-include-computer-games" title="Database of Software “Fingerprints” Expands to Include Computer Games">National Software Reference Library</a> is one of the largest publicly known collections of computer software in the world and includes a database of millions of digital signatures from known software files. That database is a critical tool for computer forensics experts and vastly speeds up the investigation of crimes involving digital evidence.</li> <li><strong>Combating the opioid epidemic:</strong> Fentanyl and other synthetic opioids kill tens of thousands of Americans each year. NIST scientists have developed <a data-entity-substitution="canonical" data-entity-type="node" data-entity-uuid="dce93abd-366d-404e-8d2d-bd9d9b0d4f36" href="/web/20240226171941/https://www.nist.gov/feature-stories/safe-efficient-reliable-new-science-fight-against-killer-drugs" title="Safe, Efficient, Reliable: New Science in the Fight Against Killer Drugs">new tools</a> that help police and forensic chemists save lives by detecting and identifying these drugs safely, efficiently and reliably.</li> <li><strong>Forensic science standards:</strong> NIST is accelerating the development and adoption of high-quality, technically sound forensic science standards by administering the <a data-entity-substitution="canonical" data-entity-type="node" data-entity-uuid="eb4a7df4-5639-44ba-b037-d31a99b5b46d" href="/web/20240226171941/https://www.nist.gov/osac" title="The Organization of Scientific Area Committees for Forensic Science">Organization of Scientific Area Committees for Forensic Science</a> (OSAC). OSAC-approved standards define minimum requirements, best practices and standard protocols that help ensure that the results of forensic analysis are reliable and reproducible. </li> <li><strong>Forensic DNA:</strong> NIST played a central role in developing the forensic DNA analysis techniques that have revolutionized crime fighting and have helped convict the guilty and exonerate the innocent. Among other things, NIST scientists have enabled <a data-entity-substitution="canonical" data-entity-type="node" data-entity-uuid="97567a34-8fcf-4064-bdc3-252ce7fce671" href="/web/20240226171941/https://www.nist.gov/news-events/news/2016/12/nist-research-enables-enhanced-dna-fingerprints" title="NIST Research Enables Enhanced DNA “Fingerprints”">enhanced DNA “fingerprints.”</a><br/> </li> </ul></div> </div> </div> </div> <div class="paragraph paragraph--type--topic-featured paragraph--view-mode--default nist-content-row--width-full bg-base-lightest margin-y-5"> <div class="grid-container"> <div class="nist-card nist-card--horizontal nist-card--horizontal-full nist-card--base-lightest"> <div class="nist-card__inner"> <div class="nist-card__image"> <a href="/web/20240226171941/https://www.nist.gov/feature-stories/safe-efficient-reliable-new-science-fight-against-killer-drugs"> <div class="entity-reference"> <figure class="nist-image"> <img src="/web/20240226171941im_/https://www.nist.gov/sites/default/files/styles/800w_x_400h/public/images/2021/03/18/Faux_Fentynal_lethal_dose_005.jpg.webp?itok=QzyMDCuD" width="800" height="400" alt="Black background. Photo of a penny. Next to the penny is a tiny amount of a white powder." loading="lazy" typeof="foaf:Image"/> <figcaption class="nist-image__caption"> <div data-caption-editable="true" class="nist-image__caption-content"> </div> </figcaption> </figure> </div> </a> </div> <div class="nist-card__title"> <h3> Safe, Efficient, Reliable: New Science in the Fight Against Killer Drugs </h3> </div> <div class="nist-card__content"> <div class="text-long"><p>“A new drug might appear, then three or six months later it’s gone, replaced by something new,” said NIST chemist and program manager Marcela Najarro. “It’s a totally different ballgame than 10 or 15 years ago.”</p> <p>To help with that issue and others, NIST researchers are giving law enforcement and public health experts new tools to combat fentanyl and other synthetic drugs.</p></div> </div> <div class="nist-card__links"> <div class="nist-card__button"> <a href="/web/20240226171941/https://www.nist.gov/feature-stories/safe-efficient-reliable-new-science-fight-against-killer-drugs" class="usa-button ">Learn more.</a> </div> </div> </div> </div> </div> </div> <div class="grid-container margin-y-4"> <div class="nist-region-heading"> <h2>News</h2> </div> <div class="margin-bottom-5"> <div class="entity-reference"> <div class="nist-card nist-card--horizontal nist-card--horizontal-full"> <div class="nist-card__inner"> <div class="nist-card__image"> <a href="/web/20240226171941/https://www.nist.gov/news-events/news/2021/06/nist-publishes-review-dna-mixture-interpretation-methods"> <div class="entity-reference"> <img loading="lazy" src="/web/20240226171941im_/https://www.nist.gov/sites/default/files/styles/600w_x_360h/public/images/2021/06/03/hero_DNA_mixtures-new.jpg.webp?itok=j0VSvOn5" width="600" height="360" alt="A dark rectangle filled with colored triangles." typeof="foaf:Image"/> </div> </a> </div> <div class="nist-card__title"> <h3><span property="schema:name">NIST Publishes Review of DNA Mixture Interpretation Methods</span> </h3> </div> <div class="nist-card__content"> <div property="schema:text" class="text-with-summary"> The National Institute of Standards and Technology (NIST) has published DNA Mixture Interpretation: A Scientific Foundation Review . This draft report, which will be open for public comment for 60 days before being published in final form, reviews the methods that forensic laboratories use to interpret evidence containing a mixture of DNA from two or more people. NIST is re-opening the public </div> </div> <div class="nist-card__links"> <div class="nist-card__button"> <a href="/web/20240226171941/https://www.nist.gov/news-events/news/2021/06/nist-publishes-review-dna-mixture-interpretation-methods" class="usa-button ">Read more</a> </div> </div> </div> </div> </div> </div> <div class="paragraph paragraph--type--dynamic-news-list-topic paragraph--view-mode--default"> <div class="views-element-container"><div class="js-view-dom-id-4de93c3397929c669e32c9318a1ce8a50750a64904edaafd042033bc10588e4b"> <div class="grid-row grid-gap-2"> <div class="nist-card tablet:grid-col-4 nist-card--topic "> <div class="nist-card__inner"> <div class="nist-card__image"> <a href="/web/20240226171941/https://www.nist.gov/news-events/news/2024/01/spotlight-forensics-videos-and-app-collecting-trace-evidence"> <div class="entity-reference"> <img loading="lazy" src="/web/20240226171941im_/https://www.nist.gov/sites/default/files/images/2024/01/08/Casting1.gif" width="720" height="405" alt="Person pours a cream-colored liquid alongside a shoeprint in the dirt." typeof="foaf:Image"/> </div> </a> </div> <div class="nist-card__title padding-y-5"> <h3><span property="schema:name">Spotlight: Forensics Videos and App for Collecting Trace Evidence</span> </h3> </div> <div class="nist-card__links"> <div class="nist-card__button"> <a href="/web/20240226171941/https://www.nist.gov/news-events/news/2024/01/spotlight-forensics-videos-and-app-collecting-trace-evidence" class="usa-button ">Read more</a> </div> </div> </div> </div> <div class="nist-card tablet:grid-col-4 nist-card--topic "> <div class="nist-card__inner"> <div class="nist-card__image"> <a href="/web/20240226171941/https://www.nist.gov/news-events/news/2023/09/spotlight-measuring-decisions-human-facial-forensic-examiners"> <div class="entity-reference"> <img loading="lazy" src="/web/20240226171941im_/https://www.nist.gov/sites/default/files/styles/800w_x_400h/public/images/2023/10/13/9faccd62-45d4-4975-b61e-87b726b80e1d.png.webp?itok=7vI4r4eB" width="800" height="400" alt="Carina Hahn sits at a workstation and looks at a computer screen." typeof="foaf:Image"/> </div> </a> </div> <div class="nist-card__title padding-y-5"> <h3><span property="schema:name">Spotlight: Measuring the Decisions of Human Facial Forensic Examiners</span> </h3> </div> <div class="nist-card__links"> <div class="nist-card__button"> <a href="/web/20240226171941/https://www.nist.gov/news-events/news/2023/09/spotlight-measuring-decisions-human-facial-forensic-examiners" class="usa-button ">Read more</a> </div> </div> </div> </div> <div class="nist-card tablet:grid-col-4 nist-card--topic "> <div class="nist-card__inner"> <div class="nist-card__image"> <a href="/web/20240226171941/https://www.nist.gov/news-events/news/2023/05/researchers-analyze-thc-breath-cannabis-smokers"> <div class="entity-reference"> <img loading="lazy" src="/web/20240226171941im_/https://www.nist.gov/sites/default/files/styles/800w_x_400h/public/images/2023/05/15/Cinnamon_Bidwell_Research_Lab_0047PC_cr.jpg.webp?itok=iys15MdM" width="800" height="400" alt="A white van with its sliding door open, parked in a lot, with mountains in the background. 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