Expert Witnesses

This page identifies a selection of expert witnesses, unaffiliated with Everytown, who have provided evidence in cases defending firearms laws against Second Amendment challenges.

Looking for Everytown’s Second Amendment experts? See our experts here. Please get in touch with any questions you might have about defending gun safety laws against Second Amendment challenges.

Age Restrictions

History: firearm regulations

Expert	Topic	Example Reports
Saul Cornell, Paul and Diane Guenther Chair in American History, Fordham University	History of age-based firearms regulations, including a discussion of the legal status of minors and their militia service, and general firearms regulatory history	Chavez v. Bonta, No. 3:19-cv-01226 (S.D. Cal.), Dkt. 134-2 (dated Sept. 11, 2023) Pinales v. Lopez, No. 1:24-cv-00496 (D. Haw.), Dkt. 35-2 (dated Dec. 20, 2024)
Brennan Gardner Rivas, Senior Postdoctoral Researcher, Center for the Study of Guns and Society, Wesleyan University	Historical context for evolving firearms regulation, with a focus on restrictions on minors	Chavez v. Bonta, No. 3:19-cv-01226 (S.D. Cal.), Dkt. 134-4 (dated Sept. 14, 2023) Rocky Mountain Gun Owners v. Polis, No. 1:23-cv-01077 (D. Colo.), Dkt. 82-4 (dated June 27, 2023)
Robert Spitzer, Distinguished Service Professor of Political Science Emeritus, State University of New York at Cortland	History of age-based firearms regulations, with a focus on university regulations	Rocky Mountain Gun Owners v. Polis, No. 1:23-cv-01077 (D. Colo.), Dkt. 82-3 (dated June 26, 2023) Pinales v. Lopez, No. 1:24-cv-00496 (D. Haw.), Dkt. 35-3 (dated Dec. 17, 2024)

History: other

Expert	Topic	Example Reports
Holly Brewer, Burke Chair of American Cultural and Intellectual History, University of Maryland	History of the legal and political status of individuals under 21, including with respect to their right to contract and their militia service	Chavez v. Bonta, No. 3:19-cv-01226 (S.D. Cal.), Dkts. 134-6, 134-7 (dated Sept. 15, 2023)
Randolph Roth, College of Arts & Sciences Distinguished Professor of History & Sociology, The Ohio State University	History of homicides and mass murders, with special attention to technological evolutions and increased youth violence	Chavez v. Bonta, No. 3:19-cv-01226 (S.D. Cal.), Dkt. 134-3 (dated Sept. 11, 2023)

Social Science: public safety risks

Expert	Topic	Example Reports
John J. Donohue III, C. Wendell and Edith M. Carlsmith Professor of Law, Stanford Law	Public safety risks of firearm possession by 18- to 20-year olds and effectiveness of gun safety laws	Chavez v. Bonta, No. 3:19-cv-01226 (S.D. Cal.), Dkt. 134-8 (dated Sept. 7, 2023)
Louis Klarevas, Research Professor, Teachers College Columbia University	Increase of mass shootings and the role of 18- to 20-year-olds in perpetrating mass shootings	Chavez v. Bonta, No. 3:19-cv-01226 (S.D. Cal.) Dkt. 134-9 (dated Sept. 13, 2023) Pinales v. Lopez, No. 1:24-cv-00496 (D. Haw.), Dkt. 35-4 (Dec. 23, 2024)
Lucy P. Allen, Senior Managing Director of NERA Economic Consulting	Statistical analysis of firearms use by 18- to 20-year-olds	Chavez v. Bonta, No. 3:19-cv-01226 (S.D. Cal.), Dkt. 111-8 (dated Mar. 16, 2023)

Social Science: adolescent & young adult development/brain science

Expert	Topic	Example Reports
Laurence Steinberg, Distinguished University Professor and Laura H. Carnell Professor of Psychology & Neuroscience, Temple University	Neurological and psychological development during adolescence and subsequent years	Rocky Mountain Gun Owners v. Polis, No. 1:23-cv-01077 (D. Colo.), Dkt. 82-5 (dated June 26, 2023) Meyer v. Raoul, No. 3:21-cv-00518 (S.D. Ill.), Dkt. 104-4 (dated Mar. 31, 2022)
Elizabeth E. Cauffman, Professor of Psychological Science, Education, and Law, University of California, Irvine	Neurological and psychological development during adolescence and subsequent years	Chavez v. Bonta, No. 3:19-cv-01226 (S.D. Cal.), Dkt. 134-10 (dated Sept. 15, 2023) Pinales v. Lopez, No. 1:24-cv-00496 (D. Haw.), Dkt. 35-5, (dated Dec. 20, 2024)

Sensitive Places

History of Firearm Regulation in Sensitive Places

Expert	Topic	Example Reports
Patrick J. Charles, Historian, U.S. Air Force Historical Support Division	History of sensitive-places regulations; history of restricting guns in relation to alcohol	May v. Bonta, Carralero v. Bonta, Nos. 8:23-cv-01696, 8:23-cv-01798 (C.D. Cal.), Dkt. 21-2 (dated Oct. 30, 2023) Goldstein v. Hochul, No. 1:22-cv-08300 (S.D.N.Y.), Dkt. 39 (dated Oct. 14, 2022)
Brennan Gardner Rivas, Senior Postdoctoral Researcher, Center for the Study of Guns and Society, Wesleyan University	History of sensitive-places regulations and public carry regulation; history of public gathering spaces; history of public transportation	May v. Bonta, Carralero v. Bonta, Nos. 8:23-cv-01696, 8:23-cv-01798 (C.D. Cal.), Dkt. 21-9 (dated Oct. 30, 2023) Schoenthal v. Raoul, No. 3:22-cv-50326 (N.D. Ill.), Dkt. 83-8 (dated Oct. 23, 2023) Schoenthal v. Raoul, No. 3:22-cv-50326 (N.D. Ill.), Dkt. 100-1 (dated June 13, 2024)
Adam Winkler, Connell Professor of Law, University of California Los Angeles	History of sensitive-places regulations, particularly in places of social and commercial congregation, places of amusement and recreation, and places where alcohol may mix with firearms	May v. Bonta, Carralero v. Bonta, Nos. 8:23-cv-01696, 8:23-cv-01798 (C.D. Cal.), Dkt. 21-12 (dated Oct. 30, 2023)
Saul Cornell, Paul and Diane Guenther Chair in American History, Fordham University	History of sensitive-places regulations with particular reference to parks, public university campuses, public gatherings, and prohibiting trespass on private property with firearms; traditional principle of preserving the peace General firearms regulatory history, including the historical police power and historical regulation of public carry	Wolford v. Lopez, No. 1:23-cv-00265 (D. Haw.), Dkt. 55-2 (dated July 13, 2023)

Leisure, Cultural, and Recreational Spaces (parks, playgrounds, museums, libraries, etc.)

Expert	Topic	Example Reports
Holly Brewer, Burke Chair of American Cultural and Intellectual History, University of Maryland	History of sensitive places relating to children, including museums, zoos, libraries, playgrounds, and sporting events	May v. Bonta, Carralero v. Bonta, Nos. 8:23-cv-01696, 8:23-cv-01798 (C.D. Cal.), Dkt. 21-1 (dated Nov. 1, 2023)
Michael Kevane, Professor of Economics, Santa Clara University	History of libraries; emergence of public libraries in the 19th century	May v. Bonta, Carralero v. Bonta, Nos. 8:23-cv-01696, 8:23-cv-01798 (C.D. Cal.), Dkt. 21-5 (dated Oct. 31, 2023)
Peter Mancall, Distinguished Professor, Andrew W. Mellon Professor of the Humanities, Professor of History, Anthropology, and Economics, University of Southern California	History of drinking establishments, places of gambling, and casinos	May v. Bonta, Carralero v. Bonta, Nos. 8:23-cv-01696, 8:23-cv-01798 (C.D. Cal.), Dkt. 21-7 (dated Oct. 31, 2023)
Terence Young, Professor Emeritus of Geography and Anthropology, Cal. State Poly. U., Pomona	History of parks and mid-19th-century emergence of parks movement	LaFave v. County of Fairfax, No. 1:23-cv-01605 (E.D. Va.), Dkt. 46-1 (dated Feb. 26, 2024)

Hospitals and Medical Facilities

Expert	Topic	Example Reports
Mary Fissell, Professor of History and History of Medicine, Johns Hopkins University	History of hospitals, development and novelty of modern hospitals	May v. Bonta, Carralero v. Bonta, Nos. 8:23-cv-01696, 8:23-cv-01798 (C.D. Cal.), Dkt. 21-3 (dated Oct. 20, 2023)
Jeanne Kisacky, independent Historian	History of hospitals, differences between modern hospitals and hospitals of founding and Reconstruction periods	May v. Bonta, Carralero v. Bonta, Nos. 8:23-cv-01696, 8:23-cv-01798 (C.D. Cal.), Dkt. 21-6 (dated Oct. 27, 2023)

Public Transportation

Expert	Topic	Example Reports
Joshua Salzmann, Professor of History, Northeastern Illinois University	History of passenger transportation, especially in towns and urban spaces; emergence of public transit systems in 20th century	May v. Bonta, Carralero v. Bonta, Nos. 8:23-cv-01696, 8:23-cv-01798 (C.D. Cal.), Dkt. 21-10 (dated Oct. 30, 2023) Schoenthal v. Raoul, No. 3:22-cv-50326 (N.D. Ill.), Dkt. 83-9 (dated Oct. 21, 2023) Schoenthal v. Raoul, No. 3:22-cv-50326 (N.D. Ill.), Dkt. 100-2 (dated June 13, 2024)

Private Property

Expert	Topic	Example Reports
Hendrik Hartog, Class of 1921 Bicentennial Professor in the History of American Law and Liberty, Professor of History, Emeritus, Princeton University	History of laws prohibiting trespass on private property with guns (private-property default rules)	Koons v. Platkin, No. 1:22-cv-07464 (D.N.J.), Dkt. 84 (dated Jan. 30, 2023)

Social Science: intimidation/chilling effects

Expert	Topic	Example Reports
Alexandra Filindra, Professor of Political Science and Psychology, University of Illinois Chicago	Conducted study of local residents and found significant intimidating and chilling effects of guns in parks and at public events in Fairfax County, Virginia	LaFave v. County of Fairfax, No. 1:23-cv-01605 (E.D. Va.), Dkt. 49-1 (dated Feb. 27, 2024)

Assault Weapons and Large-Capacity Magazines

Historical Context

Expert	Topic	Example Reports
Brian DeLay, Professor of History and Preston Hotchkis Chair in the History of the United States, UC Berkeley	History and regulation of firearms, with an emphasis on repeating firearms and the founding and Reconstruction eras	Barnett v. Raoul, No. 3:23-cv-0209 (lead) (S.D. Ill.), Dkt. 190-2 (dated May 16, 2024) Lane v. James, No. 7:22-cv-10989 (S.D.N.Y.), Dkt. 85 (dated May 15, 2024)
Randolph Roth, College of Arts & Sciences Distinguished Professor of History & Sociology, The Ohio State University	History of homicides and mass killings, with special attention to the role of new and especially dangerous weapons technologies and government restrictions enacted in response	Barnett v. Raoul, No. 3:23-cv-00209 (lead) (S.D. Ill.), Dkt. 185-6 (dated Apr. 24, 2024) Rocky Mountain Gun Owners v. Town of Superior, No. 1:22-cv-02680 (D. Colo.), Dkt. 78-13 (dated Oct. 11, 2023)
Robert Spitzer, Distinguished Service Professor of Political Science Emeritus, State University of New York at Cortland	Relationship between the development of new weapons technologies, their spread into society, and subsequent regulation by the government; historical record of restrictions on especially dangerous weapons, weapon features, and accessories	Lane v. James, No. 7:22-cv-10989 (S.D.N.Y.), Dkt. 90 (dated May 13, 2024) Barnett v. Raoul, No. 3:23-cv-00209 (lead) (S.D. Ill.), Dkt. 185-5 (dated May 8, 2024)

Empirical Analysis and Social Science

Expert	Topic	Example Reports
Lucy P. Allen, Senior Managing Director, NERA Economic Consulting	Number of rounds of ammunition used by individuals in self-defense; use of assault weapons and large-capacity magazines in public mass shootings	Barnett v. Raoul, No. 3:23-cv-00209 (lead) (S.D. Ill.), Dkt. 185-8 (dated May 9, 2024) Rocky Mountain Gun Owners v. Town of Superior, No. 1:22-cv-02680 (D. Colo.), Dkt. 78-6 (dated Oct. 12, 2023)
Stephen W. Hargarten, Professor of Emergency Medicine, Founding Dean of Global Health, and Founding Director of the Comprehensive Injury Center, Medical College of Wisconsin	Impact of being shot with an assault weapon on the human body, including through an experiment involving firing rounds from an AR-15 and other weapons into gelatin blocks serving as simulated human soft tissue	Barnett v. Raoul, No. 3:23-cv-0209 (lead) (S.D. Ill.), Dkt. 185-3 (dated May 8, 2024) Rocky Mountain Gun Owners v. Town of Superior, No. 1:22-cv-02680 (D. Colo.), Dkt. 78-10 (dated Oct. 16, 2023)
Louis Klarevas, Research Professor, Teachers College, Columbia University	Circulation and ownership of assault weapons and large-capacity magazines; mass shootings in U.S. history and the use of assault weapons and large-capacity magazines; use of assault weapons and large-capacity magazines in self-defense; impact and efficacy of restrictions on assault weapons and large-capacity magazines	Barnett v. Raoul, No. 3:23-cv-00209 (lead) (S.D. Ill.), Dkt. 190-1 (dated May 17, 2024) Ass’n of N.J. Rifle & Pistol Clubs, Inc. v. Grewal, No. 1:18-cv-10507 (D.N.J.), Dkt. 184-1, at 641-762 (dated Oct. 31, 2023) Lane v. James, No. 7:22-cv-10989 (S.D.N.Y.), Dkt. 87 (dated May 15, 2024)

Text/Linguistics

Expert	Topic	Example Reports
Dennis Baron, Professor of English & Linguistics, University of Illinois	Corpus linguistics analyses regarding (i) the historical use of the term “arms” during the founding and Reconstruction eras and (ii) the rarity of multi-shot guns in early America	Lane v. James, No. 7:22-cv-10989 (S.D.N.Y.), Dkt. 84 (dated May 9, 2024) Barnett v. Raoul, No. 3:23-cv-00209 (lead) (S.D. Ill.), Dkt. 185-10 (dated Apr. 22, 2024)

Military Experts

Expert	Topic	Example Reports
Jason Dempsey, retired U.S. Army Lieutenant Colonel	Infantry training and operations, including military use of combat rifles; comparison of military M6/M14 rifle and civilian AR-15 rifle	Barnett v. Raoul, No. 3:23-cv-00209 (lead) (S.D. Ill.), Dkt. 222-3 (dated June 8, 2024)
Craig Tucker, retired U.S. Marine Corps Colonel	Purpose, features, and uses of assault weapons and large-capacity magazines; U.S. military’s preference for semiautomatic fire over automatic fire in combat rifles; comparison of military M16/M4 rifle and civilian AR-15 rifle	Barnett v. Raoul, No. 3:23-cv-00209 (lead) (S.D. Ill.), Doc. 222-2 (dated June 7, 2024) Wiese v. Bonta, No. 2:17-cv-00903 (E.D. Cal.), Doc. 135-18 (dated Apr. 28, 2023) Rupp v. Bonta, No. 8:17-cv-00746 (C.D. Cal.), Doc. 151-15 (dated Jan. 6, 2023)