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Search Publications by: John Butler (Fed)

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Displaying 1 - 25 of 107

Inconclusive Decisions and Error Rates in Forensic Science

May 4, 2024
Author(s)
Henry Swofford, Steven Lund, Hariharan K. Iyer, John Butler, Johannes A. Soons, Robert M. Thompson, Vincent Desiderio, JP Jones, Robert Ramotowski
In recent years, there has been discussion and controversy relating to the treatment of inconclusive decisions in forensic feature comparison disciplines when considering the reliability of examination methods and results. In this article, we offer a brief

Digital Investigation Techniques: A NIST Scientific Foundation Review

November 21, 2022
Author(s)
James R. Lyle, Barbara Guttman, John Butler, Kelly Sauerwein, Christina Reed, Corrine Lloyd
This document is an assessment of the scientific foundations of digital forensics. We examined descriptions of digital investigation techniques from peer-reviewed sources, academic and classroom materials, technical guidance from professional organizations

Revision of the SNPforID 34-plex forensic ancestry test: Assay enhancements, standard reference sample genotypes and extended population studies

May 3, 2021
Author(s)
John Butler, Manuel Fondevila, Carla Santos, Ana Freire, Christopher Phillips, M Lareu, Peter Vallone
A revision of an established 34 SNP forensic ancestry test has been made by swapping the under- performing rs727811 component SNP with the highly informative rs3827760 that shows a near-fixed East Asian specific allele. We collated SNP variability data for

NIST Scientific Foundation Reviews

December 18, 2020
Author(s)
John M. Butler, Hariharan K. Iyer, Richard A. Press, Melissa Taylor, Peter Vallone, Sheila Willis
The National Institute of Standards and Technology (NIST) is a scientific research agency that works to advance measurement science, standards, and technology and that has been working to strengthen forensic science methods for almost a century. In recent

Decade(s) of Development in Forensic Science

July 15, 2020
Author(s)
John Butler
On November 12, 2019, at a special anniversary conference entitled "Forensic Science: A Decade of Developments" held at the American Association for the Advancement of Science (AAAS), I provided an overview of developments across the forensic science

DNA mixture interpretation principles: insights from the NIST scientific foundation review

July 1, 2020
Author(s)
John Butler, Hariharan K. Iyer, Richard A. Press, Melissa Taylor, Peter Vallone, Sheila Willis
DNA mixture interpretation has become more challenging in recent years due to several factors including submission of more touch evidence samples to aid investigations and generation of more sensitive DNA test results with new STR typing kits. This

DNA Error Rates

December 7, 2016
Author(s)
John Butler
The 1993 U.S. Supreme Court ruling in Daubert vs. Merrell-Dow Pharmaceuticals insists on knowledge regarding error rates and their application when evidence is introduced into court [1]. The 1996 National Research Council (NRC II) report The Evaluation of

DNA Commission of the International Society for Forensic Genetics: Recommendations on the validation of software programs performing biostatistical calculations for forensic genetics applications

September 4, 2016
Author(s)
Michael D. Coble, John S. Buckleton, John M. Butler, Barbara Guttman
The use of biostatistical software programs to assist in data interpretation and calculate likelihood ratios is essential to forensic geneticists and part of the daily case work flow for both kinship and DNA identification laboratories. Previous

Evaluation of Forensic DNA Mixture Evidence: Guidelines for Evaluation, Interpretation, and Statistical Calculations using the Combined Probability of Inclusion

August 31, 2016
Author(s)
Frederick R. Bieber, John Buckleton, Bruce Budowle, John Butler, Michael D. Coble
The evaluation and interpretation of forensic DNA mixture evidence faces greater interpretational challenges due to increasingly complex mixture evidence. Such challenges include: casework involving low quantity or degraded evidence leading to allele and

Recent Activities of the National Commission on Forensic Science

July 1, 2016
Author(s)
John Butler
In February 2013, the U.S. Department of Justice (DOJ) and the National Institute of Standards and Technology (NIST) announced a partnership that included formation of the National Commission on Forensic Science (NCFS) and what is now the Organization of

NIJ Funding: Supporting Scientists, Supporting Innovation

December 1, 2015
Author(s)
John Butler
In this invited submission to the NIJ Journal, I reflect on the role that National Institute of Justice (NIJ) funding has played in my career in forensic science. Early experiences at the FBI Laboratory are discussed along with the benefits of

STR Allele Sequence Variation: Current Knowledge and Future Issues

July 6, 2015
Author(s)
Katherine Gettings, Rachel A. Aponte, Peter Vallone, John M. Butler
This article reviews what is currently known about short tandem repeat (STR) allelic sequence variation in and around the twenty-four loci most commonly used throughout the world to perform forensic DNA investigations. These STR loci include D1S1656, TPOX

The Future of Forensic DNA Analysis

June 22, 2015
Author(s)
John M. Butler
The author's thoughts and opinions on where the field of forensic DNA testing is headed for the next decade are provided in the context of where the field has come over the past 30 years. Like the Olympic motto of "faster, higher, stronger", forensic DNA

Advanced Topics in Forensic DNA Typing: Interpretation (textbook)

September 1, 2014
Author(s)
John M. Butler
This book is primarily intended for DNA analysts or those trying to understand what a DNA analyst does in his or her review of forensic DNA data that was obtained by polymerase chain reaction (PCR) amplification and short tandem repeat (STR) typing via

Some Journal Metrics for Forensic Science International: Genetics

October 2, 2013
Author(s)
John M. Butler
Forensic Science International: Genetics, which is the official journal of the International Society for Forensic Genetics, has grown in readership and impact factor since its introduction in 2007. This article reviews some metrics of the 32 issues

The Triad of Scientific Publication: Reading, Writing, and Reviewing

October 2, 2013
Author(s)
John M. Butler
A workshop on scientific publication was presented at the 2013 ISFG conference by the author, who has written four widely-used textbooks and 150 peer-reviewed articles and invited book chapters. This article is a summary of key points made during the

Biology and Genetics of New Autosomal STR Loci Useful for Forensic DNA Analysis

August 19, 2013
Author(s)
John M. Butler, Carolyn R. Steffen
Short tandem repeats (STRs) are regions of tandemly repeated DNA segments found throughout the human genome that vary in length (through insertion, deletion, or mutation) with a core repeated DNA sequence. Forensic laboratories commonly use tetranucleotide

Haplotype Data for 23 Y-chromosome markers in four U.S. population groups

May 1, 2013
Author(s)
Michael D. Coble, Carolyn R. Steffen, John M. Butler
The PowerPlex Y23 kit contains 23 Y-chromosomal loci including all 17 of the markers in the Yfiler Y-STR kit plus six additional markers: DYS481, DYS533, DYS549, DYS570, DYS576, and DYS643. We have typed 1032 unrelated population samples from four self