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Deffebach Matt

Matthew Thomas Deffebach

As chair of our OSHA and Workplace Disasters Practice Group, Matthew Deffebach helps clients use preventative measures to minimize claims and reduce exposure to litigation. Matt is board certified in labor and employment law by the Texas Board of Legal Specialization and is recognized in Chambers USA, 2019-2023 (Chambers and Partners) for OSHA nationally and labor and employment in Texas.

As an employment litigator and former chair of our Labor and Employment Practice Group, Matt has successfully handled hundreds of agency proceedings, arbitrations, and lawsuits in state and federal court concerning ERISA, discrimination, harassment, retaliation, leave and accommodation, ADA public access, wage and hour (including FLSA collective actions), executive compensation, wrongful termination, privacy, social media, and others. Clients also turn to Matt for advice on issues related to employment law, and he is frequently enlisted to conduct workplace investigations based on employee complaints of misconduct. He regularly speaks about employment law compliance and has conducted numerous trainings for clients and appeared at dozens of seminars and conferences.

Matt’s strong national OSHA litigation practice is of particular value to clients such as Home Depot, whom he has served as National OSHA counsel for 16 years. He has represented clients in 30 states across the U.S., and has familiarity with state OSHA programs, particularly in California where he has handled numerous contested cases involving Cal/OSHA. Matt has also successfully defended clients in OSHA administrative trials, including recent trials on PPE in California, powered industrial trucks in Utah, recordkeeping in Iowa, and other regulatory matters in four separate trials in California.

As a general commercial litigator and previous co-chair of the firm’s Litigation Practice Group, Matt handles contract disputes and non-subscriber negligence lawsuits and arbitrations. He also routinely assists clients on misappropriation of trade secret matters and unfair competition claims regarding noncompetition and non-solicitation agreements.

Matt has been recognized by Benchmark Litigation (Euromoney Institutional Investor PLC) as a “Labor & Employment Star – South,” 2019-2021 and a “Labor & Employment Star – West,” 2019.

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Employment Litigation

  • Lagos, et al. v. Cogent Communications (S.D. Tex. 2014) (granting Motion to Decertify nationwide collective action)
  • Ihegwood v. Harris County Hospital District, 929 F. Supp. 2d 635 (S.D. Tex. 2013) (granting summary judgment on Title VII and ADA claims)
  • Peterson Group v. PLTQ Lotus Group, 417 S.W.3d 46 (Tex. App. – Houston [1st Dist.] 2013) (reversing on alter ego finding)
  • Grenado v. White Cap Construction, (El Paso County Court of Law 2012) (granting summary judgment on Chapter 21 discrimination and retaliation claims)


  • Defense of breach of contract
  • Defense of ERISA denial of benefits
  • Defense of non-subscriber negligence
  • Defense of fraud, breach of contract, and breach of fiduciary duty
  • Defense of non-subscriber negligence

Occupational Safety and Health (OSHA) and Workplace Disasters 

  • Assisted a client with an investigation into a five-alarm fire, which caused over $35 Million in damages
  • Successfully defended clients in OSHA administrative trials including fatality matter in Texas, PSM inspection in Texas, fall protection case in California, state-wide machine guarding case in Maryland, and PPE matter in California
  • Defended a national employer in two separate OSHA proceedings where the Department of Labor withdrew its citations entirely on the eve of trial in both matters
  • Fellow, Texas Bar Foundation
  • Trinity University Alumni Association
  • American Society of Safety Engineers
  • Retail Industry Leaders Association
  • American Bar Association OSHA Subcommittee
  • Recognized as a leader in Employment, Lexology Client Choice Awards, Lexology, 2022
  • Recognized in Chambers USA, Chambers and Partners, for Labor & Employment (Texas), 2019-2023; for Occupational Safety and Health (Nationwide), 2022-2023.
  • Named a "Labor & Employment Star," Benchmark Litigation, Euromoney Institutional Investor PLC, 2019-2021.
  • Recognized by The Best Lawyers in America, Woodward/White, Inc., in Litigation - Labor and Employment, 2015-2024, Employment Law- Management, 2023-2024. 
  • Included in the Houston Business Journal’s 2015 Law Guide of Houston’s Largest Law Firms and Their Top Lawyers, American City Business Journals, 2015.
  • Selected for Inclusion in Texas Super Lawyers, Thomson Reuters, in Employment and Labor, 2010-2023.
  • Received the 2013 International Law Office (ILO) and Lexology Client Choice award as the sole recipient in the Employment and Labor category in Texas, Globe Business Publishing Ltd, 2013.
  • Named a "Rising Star" and one of 10 employment lawyers under 40 to watch, Law360 by Portfolio Media, Inc., 2010.
  • Selected for inclusion in Texas Super Lawyers – Rising Stars Edition, Thomson Reuters, 2005-2010.
  • Certified by the Texas Board of Legal Specialization as a labor and employment law specialist.
  • "OSHA Announces Expansion of Submission Requirements for Injury and Illness Data for High-Hazard Industries,” author, OSHA Client Update, August 3, 2023.
  • "OSHA Launches National Emphasis Program For Warehouses and Distribution Centers,” author, OSHA Client Update, August 1, 2023.
  • “Employers Should Prepare for Increased Fall-Related Inspections,” author, OSHA Client Update, June 2, 2023.
  • “Ethical Issues in Hiring Decisions and Legal Issues Using AI,” “OSHA Updates,” presenter, Employment Law Updates, San Antonio, TX, May 9, 2023.
  • “Sticky Employee Leave Issues,” presenter, Employment Law Updates, Houston, TX, April 27, 2023.
  • “Ethical Issues in Hiring Decisions and Legal Issues Using AI,” “What Is Happening with OSHA?” presenter, Employment Law Updates, Dallas, TX, April 4, 2023.
  • “OSHA Expands Enforcement Measures to Deter Violations,” author, OSHA Client Update, February 17, 2023.
  • "Cal/OSHA Standards Board Adopts COVID-19 Prevention Non-Emergency Regulations,” author, OSHA Client Update, December 28, 2022.
  • “OSHA Issues Notice of Potential Changes to Process Safety Management of Highly Hazardous Chemicals,” author, OSHA Client Update, September 28, 2022.
  • “Back to the Office: Implementing a Successful Strategy,” speaker, French American Chamber of Commerce – Texas, May 5, 2021.
  • “2021 OSHA COVID-19 Workplace Requirements,” presenter, Training Leader, March 16, 2021.
  • "The Impact of a Biden Administration on Texas Businesses," presenter, The Texas Lawbook webinar, March 2, 2021.
  • “OSHA Issues Revised COVID-19 Guidance for Workplaces,” presenter, myLawCLE, February 22, 2021.
  • “Strange Bedfellows: The Interplay Between CAL and Federal OSHA and OSHA’s Short-Term Agenda,” co-presenter, RILA’s Asset Protection Webinar Series, August 13, 2020.
  • “Legal Aspects of Safety and Effective Communication in Legal Proceedings,” presenter, The Center for Risk Management at College of the Mainland, May 29, 2020.
  • “Employers Providing Face Masks Should Review Their Health and Safety Obligations,” co-author, LexisNexis, April 6, 2020.
  • “COVID-19 and OSHA,” co-author, LexisNexis, March 18, 2020.
  • “CAL OSHA, OSHA, and Labor and Employment Update,” presenter, National Armored Car Association’s Annual Meeting, San Diego, California, October 1, 2019.
  • “The Lawyer, the Witness and the War Room: Effective Communication and Preparation in Litigation,” presenter, National Safety Council’s 2019 Congress & Expo, San Diego, California, September 10, 2019.
  • “Understanding Ethical Responsibilities and Legal Liabilities in Safety,” presenter, The Center for Risk Management at College of the Mainland, La Marque, Texas, March 22, 2019.
  • “OSHA Updates for Employment Attorneys,” presenter, Houston Bar Association’s Labor & Employment Section’s Lunch Meeting, Houston, Texas, March 18, 2019.
  • “How to Avoid Turning Your Investigation Into a Liability,” presenter, Safety 2018, the American Society of Safety Engineers’ Professional Development Conference, San Antonio, Texas, June 5, 2018.
  • “Successfully Navigating Safety-Related Investigations and Legal Proceedings,” presenter, The Center for Risk Management at College of the Mainland, La Marque, Texas, March 2, 2018.
  • “The Big Event: The OSHA Trial,” presenter, The American Society of Safety Engineers’ Safety 2017 Professional Development Conference & Exposition, Denver, Colorado, June 20, 2017.
  • “What Information Can an Employer Legally and Ethically Use in Making Employment Decisions,” presenter, The Gulf Coast Symposium on HR Issues, Houston, Texas, May 10, 2017.
  • “Legal Aspects of Safety,” presenter, The Center for Risk Management at College of the Mainland, La Marque, Texas, April 20, 2017.
  • "Helping Employer Clients Stay in Compliance with the Ever-Changing Realm of Employment Law," Chapter author,  Aspatore Books 2016-2017 edition of Complying with Employment Regulations: Leading Lawyers on Analyzing Legislation and Adapting to the Changing State of Employment Law.
  • “Personal and Corporate Safety-Related Liability: Who and What can be Sued?” presenter, November ASSE & AIHA Chapter Meeting, Houston, Texas, November 3, 2016.
  • “We Have to Do WHAT? Recent Developments in OSHA Law and Practical Advice for Addressing Them,” presenter, 2016 Asset Protection Summer Webinar Series - Retail Industry Leaders Association, webinar, August 30, 2016.
  • "The Relationship Between Legal and Safety." presenter, National ASSE Conference, Atlanta, Georgia, June 27, 2016
  • “We Have to Do WHAT? Recent Developments in OSHA Law and Practical Advice for Addressing Them.” presenter, Retail Asset Protection Conference, Dallas, Texas, April 18, 2016.
  • “Personal and Corporate Safety-Related Liability: Who and What Can Be Sued?” presenter, 2016 Indiana Safety and Health Conference & Expo, Indianapolis, Indiana, March 21, 2016.
  • “More Claims, More Problems: Ethical Issues in Workplace Investigations,” presenter, Ethics in Employment Law, Houston, Texas, October 29, 2015.
  • “Ethics in Workplace Investigations,” presenter, Ethical Principles for Corporate Counsel in Energy, Houston, Texas, October 15, 2015.
  • “OSHA Update 2015,” presenter, Haynes and Boone, Houston, Texas, August 19, 2015.
  • “OSHA Law Update: Recent Activity, New Rules and Preserving the Attorney-Client Privilege,” presenter, Retail Industry Leaders Association (RILA) Retail Asset Protection Conference, Orlando, Florida, May 4, 2015.


J.D., University of Houston Law Center, 1999

B.A., Political Science and Speech Communication, Trinity University, 1993, cum laude



Court Admissions

U.S. Court of Appeals for the Fifth Circuit

U.S. District Court for the Eastern District of Texas

U.S. District Court for the Northern District of Texas

U.S. District Court for the Southern District of Texas

U.S. District Court for the Western District of Texas

Kapoor, Mendoza and Deffebach in Westlaw Today: A Company's Environmental, Health and Safety Team Co [...]
April 15, 2024

Haynes and Boone, LLP Partners Mini Kapoor, Mary Mendoza and Matthew Deffebach authored an article for Westlaw Today discussing how a company's Environmental, Health & Safety (EHS) team could play a significant role in assessing, monitoring and achieving the company's Environmental Social Governance goals. Read an excerpt below. Environmental Social Governance (ESG) may be used to assess a company [...]