Thomas P. Bernier
Baltimore, MD
410.783.7004 Direct
410.783.7221 Facsimile
Assistant(s): Mallie J. Cookus
  • >


Thomas Bernier is a partner and trial attorney in DeHay & Elliston’s Toxic Tort and Environmental Practice Groups and serves as the firm’s National Legionnaires’ Disease Litigation Coordinating Counsel. He is certified as a water safety and management specialist by American Society of Sanitary Engineers (ASSE) and is the first and likely only attorney in the country defending Legionnaires' disease claims holding this certification. With more than four decades of experience successfully defending complex and high-profile civil and criminal cases in the state and federal courts throughout Maryland and Washington, D.C., and in other parts of the country, he focuses his civil practice on the defense of toxic tort actions against companies in a wide range of industries, with particular concentration on claims alleging exposure to Legionella, asbestos, lead paint, carbon monoxide, and mold. Tom also has extensive experience defending personal injury, premises liability, and product liability. He is a frequent author and presenter on personal injury defense and other topics in his areas of concentration. For additional information on DeHay & Elliston’s Legionnaires’ disease defense practice, go to:

Further demonstrating his trial prowess and litigation capabilities, Tom has litigated hundreds of serious criminal cases over the past 40-plus years, including two capital cases. He is the author of Defending Allegations of Sexual Child Abuse in Maryland, an original treatise published in 2004 that highlights a subspecialty of his criminal practice and is used by the District Court of Maryland in the training of District Court Commissioners. Tom has been asked to testify before the House and Senate Judiciary Committees of the Maryland General Assembly on matters of criminal law and evidence, and he has counseled the writing staff of NBC’s Law and Order: Special Victims Unit on the perspective of a defense attorney in a sex crimes case and on technical accuracy of potential script ideas.

Working pro bono on the ABA “Death Penalty Project,” Tom obtained a life-without-parole verdict in death penalty resentencing jury trial in Miller County, Arkansas as part of a three- lawyer defense team.

In January 2024, Tom completed the Maryland State Bar Association’s mediation training course required to mediate cases for the circuit and district courts of Maryland and has expanded his practice to include mediation services. With 40 years of litigation experience practice –17 representing plaintiffs and 23 representing defendants – he has developed a unique understanding of both the plaintiff and defense perspectives in contested cases. Because he has tried over a hundred jury trials to verdict, Tom also fully appreciates the costs and uncertainty of taking a case to verdict. He has participated in hundreds of mediations and evaluated and settled thousands of cases. Additionally, decades of experience litigating complex, multidefendant cases has also imparted Tom with the skill to navigate the myriad contribution and indemnity issues inherent in cross- and third-party claims between joint tortfeasors. Tom has been appointed by Circuit Court for Baltimore County as a Court approved mediator.  He is available for both in-person and virtual mediation sessions.


Martindale-Hubbell Peer Judicial and Review Rating: AV Preeminent; Top-Rated Lawyer in Mass Torts (2014-16) and Insurance Law (2014-16)

Best Lawyers in America
 - Lawyer of the Year (Baltimore), 2018, 2020
 - Product Liability Litigation - Defendants, 2016-24
 - Insurance Litigation, 2016-24

Expert Network Distinguished© Lawyer
Top 100 Trial Lawyers in Maryland, American Academy of Trial Attorneys
Maryland Super Lawyers, 2014-24
Selected for Rue Ratings' "Best Attorneys of America"
Top 100 Litigation Lawyers in Maryland, American Society of Legal Advocates

Bar Admissions

District of Columbia
U.S. District Court for the District of Maryland
U.S. District Court for the District of Columbia
U.S. Court of Appeals for the Fourth Circuit


University of Baltimore School of Law, J.D., 
University of Notre Dame, B.A., 

Associations & Memberships

Maryland State Bar Association
District of Columbia Bar Association
Maryland Program for Mediator Excellence (MPME)


Chief Hearing Officer, Baltimore Department of Human Resources Civil Service Commission (2006-2018)
Peer Review Committee Member, Attorney Grievance Commission of Maryland
Mentor, University of Baltimore School of Law Mentor Program
Running coach for 2012 Olympic pentathlon competitor
Member, Board of Trustees Oldfields School


“Is There a Legal Standard of Care for Legionnaires’ Disease?” (Author) Law360, October 23, 2019

Quoted in “Legionnaires’ Disease: 95 Confirmed Cases, 1 Dead. Can They Sue?” Citizen Times, October 4, 2019

Featured on “Attorney Breaks Down Legal Side of Legionnaires’ Disease,” WENY-TV, October 3, 2019

“Insuring Legionella Risks” (co-author), Risk Management, January/February 2019

“Defense Strategies for Alternative Causation Arguments in Asbestos Cases” (co-author), i, August 29, 2018

“New Evidence That Carbon Nanotubes Have Potential to Cause Mesothelioma” (co-author), ARIAS-US Quarterly, Spring 2018

“Nanotechnology: The Next Mass Tort?” (co-author), ABA Mass Torts Litigation, August 15, 2017

“New EPA Reporting Rule Requires Companies to Register Chemicals Containing Nanoscale Materials,” DRI Toxic Torts, June 9, 2017

"The Standard of Care Defense in Emerging Toxic Tort Claims” (co-author), DRI Toxic Tort and Environmental Law Compendium, Spring 2017

Litigation Trend Could Snag Utilities” (quoted), American Water Works Association, January 3, 2017

What General Counsel Should Know About Legionnaires’ Disease” (co-author), Today’s General Counsel, October 2015

Co-Author, “Sound the Alarm: Containing the Increasing Incidence of High Demands in Low-Exposure Carbon Monoxide Claims,” Claims Management, October 14, 2014

“The Standard of Care Defense in Emerging Toxic Tort Claims” (co-author), DRI For the Defense, April 2014

“Legionnaires’ Disease and Premises Liability” (co-author), Claims Management, June 12, 2013

“When Man’s Best Friend Bites” (co-author), Claims Management, November 2, 2012

“New ASHRAE Standard Dictates Legionnaires’ Disease Prevention,” Indoor Environment Connection, May 2, 2012


“Legionnaires’ Disease: Legal Risks & Claims Management Strategies” Presenter, NCADA 2020 Winter Workshop, Durham, NC, January 31, 2020

Thomas P. Bernier Discusses Legionnaires’ Disease with Perrin Conferences, December 2, 2019

Quoted in “As Legionnaires’ Disease Cases Surge, Lawsuits Pile Up,” Circle of Blue, November 7, 2019

“Nursing Home ALF Litigation” Co-Presenter, DRI Seminar, Chicago, Illinois, September 20, 2019

Presenter, “The State of the Bankruptcy Trusts,” Perrin National Asbestos Conference, San Francisco, CA, October 1, 2018

“Legal Risks Associated with Legionnaire’s Disease and Waterborne HAIs,” NALCO Legal Risks of Legionella and Waterborne Infections in Healthcare Facilities Conference, Philadelphia, PA, November 9, 2017

“Game-Changing Asbestos Developments: This Past Year’s Most Significant Verdicts and Decisions,” Goldberg Segalla Toxic Torts and Environmental Law Seminar, May 23, 2017

“What’s Coming Now and in the Future: A Roundtable Chat on Emerging Issues in Talc, Nanotechnology, and Marijuana,” Goldberg Segalla Toxic Torts and Environmental Law Seminar, May 23, 2017

“Emerging Risks – New and Evolving, Nanotechnology,” ARIAS U.S. Spring Conference, Naples, FL, May 3, 2017

“Legal Risks Associated with Legionnaire’s Disease and Waterborne Associated Infections,” Legionnaire’s Disease and Waterborne Associated Infections: Strategies to Reduce Risk, Baltimore, MD, April 20, 2017

“Defending Foodborne Illness Claims,” Client presentation, Dover, NH, March 21, 2017

“Emerging Legal Issues: A Lead and Legionella Trend,” American Water Works Association, December 15, 2016

“Legionnaires’ Disease: Legal Risks and Claims Management Strategies,” Toxic Tort/Environmental Scouting Report Seminar, Chicago, IL, October 18, 2016

“The ‘Low Dose’ Defense in Asbestos-Induced Mesothelioma Cases,” Toxic Tort/Environmental Scouting Report Seminar, Chicago, IL, October 18, 2016

“Legal Challenges of Legionella,” Rollins School of Public Health at Emory University’s From Watersheds to Shower Heads: A Workshop on Legionella Research and Policy, Atlanta, May 26, 2016

“Legionella and Other Waterborne Pathogens: Recognition, Evaluation, and Control,” American Industrial Hygiene Conference & Exposition (AIHce), Baltimore, MD, May 21, 2016

“Recognition, Evaluation, and Control of Legionella in Building Water Systems,” American Industrial Hygiene Conference and Exposition (AIHce), Salt Lake City, UT, June 3, 2015

“Risk Management, Liability, and Coverage Concerns Arising From Emerging and Resurgent Pathogens Such as Ebola, Enterovirus D68, CRE, and Measles,” Environmental and Emerging Claim Manager Association Annual Meeting, Orlando, FL, April 29 to May 1, 2015

“Legionnaires’ Disease: A Critical Update at a Critical Moment,” Emerging and Environmental Claims Managers Association, Captiva Island, FL, April 30 to May 2, 2014

“The Preparation and Trial of a Personal Injury Case,” Maryland State Bar Association, January 23 and 30, 2014

“The Low Dose Defense in Asbestos-Induced Mesothelioma Cases,” The Emerging and Environmental Claims Managers Association (EECMA) 2013 Conference and Meeting, Captiva Island, FL, May 3, 2013

“Legionnaires’ Disease: Emerging Trends,” WCD Group, New York, NY, February 21, 2013

“Perspectives on Using Strict Liability to Reduce Dog Bites in Maryland,” Maryland State Bar Association Annual Fall Dinner, Sheraton Columbia Town Center, Columbia, MD, September 27, 2012

“Legionella Roundtable,” Building Owners and Managers Association (BOMA) Baltimore Chapter Education Program, Baltimore, MD, June 14, 2012

“Legionnaires’ Disease: Alive and Well,” Emerging and Environmental Claims Managers Association (EECMA) 2012 Conference and Meeting, Captiva Island, FL, May 4, 2012

“Defenses in Sexual Offenses and Child Abuse Cases,” Felony Division of the Baltimore City Office of the Public Defender, April 18, 2012

“Asbestos Trial Program,” Perrin Conferences Mock Trial, Wausau, WI, January 23, 2012

“Deposition Practice and Procedure,” Maryland State Bar Association CLE, December 15, 2011

“When Your Custody Case Becomes Criminal,” Maryland State Bar Association Annual Meeting, Ocean City, MD, June 15, 2007

“When Your Custody Case Becomes Criminal,” Joint Meeting of the Criminal and Family Law Sections of the Baltimore County Bar Association, October 2006


Co-Presenter, “COVID-19 and the Impact on Long-Term Care Facilities,” GS Webinar Series, April 10, 2020

Presenter, “Legionnaires’ Disease: Legal Risks and Claims Management Strategies,”  Perrin Conference Webinar, Monday, December 2, 2019

Presenter, “Legionnaires’ Disease: Legal Risks and Claims Management Strategies,” GS TTEL Webinar Series, July 18, 2019

Presenter, “Alternative Causes of Mesothelioma: Radiation (Part 1 of 3),” TTEL Webinar Series, September 20, 2018