L. Mark Walker
About L. Mark Walker
L. Mark Walker is a lawyer based in Oklahoma City, OK and has been recognized in The Best Lawyers in America® since 2003. L. Mark Walker is recognized in the following practice areas:
- Oklahoma City, Oklahoma
- CleanTech Law
- Energy Law
- Energy Regulatory Law
- Environmental Law
- Litigation - Environmental
- Mass Tort Litigation / Class Actions - Defendants
- Natural Resources Law
- Oil and Gas Law
- Water Law
Current Firm: Crowe & Dunlevy
Education: University of Oklahoma, J.D., graduated 1983
Location: Oklahoma City, OK
It takes just a few minutes to optimize your profile for clients looking to engage and lawyers who are ready to refer.
Activate your profile and highlight why your peers recognized in Best Lawyers today.
Nearby Lawyers
Michael J. Heron is a Partner in our Oklahoma City office with over 30 years of legal experience. He specializes in protecting the rights of individuals and businesses in civil cases involving medical malpractice, professional liability, construction, transportation, and insurance matters. Mike represents hospitals, practice groups, physicians, nurses, and other health care professionals in a wide range of litigation, policies and procedures, compliance, investigations, business transactions,...
Steven J. Johnson is a top attorney recognized by Best Lawyers in the practice area(s) of Medical Malpractice Law - Defendants. Steven J., who practices law in Oklahoma City, Oklahoma, has been recognized since 2024. This recognition is based on an exhaustive peer-review survey, reflecting the high esteem in which Steven J. is held by other top lawyers in the same geographic and legal practice area.
Amy brings more than 25 years of experience in trial and appellate practice, with a career shaped by leadership roles and in-depth involvement in Family Law matters. Her background includes serving with Oklahoma Child Support Services, where she helped lead the state’s implementation of the Uniform Parentage Act, as well as her service as a District Judge for the Cherokee Nation. This range of experience provides her with a well-rounded understanding of family law issues affecting indiv...
Over 30 years representing defendants in business and complex litigation, including commercial and employment disputes, securities, class action and antitrust cases. Has lectured in the areas of trial practice, civil procedure, and insurance law. Former President of the Oklahoma County Bar Association, 2007-08.
Amy Sherry Fischer is a top attorney recognized by Best Lawyers in the practice area(s) of Commercial Litigation and Product Liability Litigation - Defendants. Amy Sherry, who practices law in Oklahoma City, Oklahoma, has been recognized since 2020. This recognition is based on an exhaustive peer-review survey, reflecting the high esteem in which Amy Sherry is held by other top lawyers in the same geographic and legal practice area.
John D. Robertson is a top attorney recognized by Best Lawyers in the practice area(s) of Corporate Law, Mergers and Acquisitions Law and Securities / Capital Markets Law. John D., who practices law in Oklahoma City, Oklahoma, has been recognized since 2007. This recognition is based on an exhaustive peer-review survey, reflecting the high esteem in which John D. is held by other top lawyers in the same geographic and legal practice area.
Larry D. Ottaway is a top attorney recognized by Best Lawyers in the practice area(s) of Bet-the-Company Litigation, Commercial Litigation, Legal Malpractice Law - Defendants, Litigation - Insurance, Mass Tort Litigation / Class Actions - Defendants, Medical Malpractice Law - Defendants, Personal Injury Litigation - Defendants and Product Liability Litigation - Defendants. Larry D., who practices law in Oklahoma City, Oklahoma, has been recognized since 2015. This recognition is based on an e...
J. Leslie LaReau is a top attorney recognized by Best Lawyers in the practice area(s) of Tax Law and Trusts and Estates. J. Leslie, who practices law in Oklahoma City, Oklahoma, has been recognized since 2012. This recognition is based on an exhaustive peer-review survey, reflecting the high esteem in which J. Leslie is held by other top lawyers in the same geographic and legal practice area.
Lori F. Winland is a top attorney recognized by Best Lawyers in the practice area(s) of Employment Law - Management and Litigation - Labor and Employment. Lori F., who practices law in Oklahoma City, Oklahoma, has been recognized since 2026. This recognition is based on an exhaustive peer-review survey, reflecting the high esteem in which Lori F. is held by other top lawyers in the same geographic and legal practice area.
Courtney K. Warmington is an advisory director in Crowe & Dunlevy’s Labor and Employment Section. Since joining the group in 1999, Ms. Warmington has successfully represented management in cases brought by employees under Title VII of the Civil Rights Act, the Americans With Disabilities Act, the Age Discrimination in Employment Act, the Family and Medical Leave Act, Oklahoma’s Workers’ Compensation laws, and the Fair Labor Standards Act. In addition to her litigation pr...
Explore and Learn
The Family Law Loophole That Lets Sex Offenders Parent Kids
by Bryan Driscoll
Is the state's surrogacy framework putting children at risk?
Unenforceable HOA Rules: What Homeowners Can Do About Illegal HOA Actions
by Bryan Driscoll
Not every HOA rule is legal. Learn how to recognize and fight unenforceable HOA rules that overstep the law.
Best Lawyers 2026: Discover the Honorees in Brazil, Mexico, Portugal, South Africa and Spain
by Jamilla Tabbara
A growing international network of recognized legal professionals.
Holiday Pay Explained: Federal Rules and Employer Policies
by Bryan Driscoll
Understand how paid holidays work, when employers must follow their policies and when legal guidance may be necessary.
Can a Green Card Be Revoked?
by Bryan Driscoll
Revocation requires a legal basis, notice and the chance to respond before status can be taken away.
What Is the Difference Between a Will and a Living Trust?
by Bryan Driscoll
A practical guide to wills, living trusts and how to choose the right plan for your estate.
US Tariff Uncertainty Throws Canada Into Legal Purgatory
by Bryan Driscoll
The message is clear: There is no returning to pre-2025 normalcy.
New Texas Family Laws Transform Navigating Divorce, Custody
by Bryan Driscoll
Reforms are sweeping, philosophically distinct and designed to change the way families operate.
The 2026 Best Lawyers Awards in Chile, Colombia and Puerto Rico
by Jamilla Tabbara
The region’s most highly regarded lawyers.