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John appears in the 
Top 100 Attorneys Magazine

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John P. Mahoney, Esq.

For nearly three decades, John P. Mahoney has utilized his extensive legal experience to protect, defend, and enhance the federal careers of clients in all 50 states, as well as around the world. As a preeminent, AV-rated and award-winning attorney, he has represented thousands of federal employees and contractors in both security clearance appeals and federal employment law (FEL) matters. John has won or settled several multimillion-dollar class action suits on behalf of federal employees, as well as individual cases with awards of more than a million dollars for his firm’s clients.


Among John’s notable victories are Krzych v. Secretary, Dept. of the Army, in which he successfully proved that the Army had discriminated against his client based on her gender, national origin, and age. In Cohen v. Department of Homeland Security (ICE), he litigated against the Department of Homeland Security (DHS), Immigration and Customs Enforcement (ICE) and won a U.S. Merit Systems Protection Board (MSPB) decision, reversing his client’s termination from federal employment, returning her to duty, and resulting in his client receiving full back pay plus interest and other benefits. In another triumphant outcome in a case before the U.S. Equal Employment Opportunity Commission, Hamilton v. Department of the Air Force, John secured over a $1 million settlement on behalf of his federal employee client, which reversed his termination with full backpay, benefits, interest, a corrected record, and a retroactive promotion, and in Wheller et al. v. DC, he successfully represented the plaintiffs and won a multimillion-dollar federal employment law class action on summary judgment in the U.S. District Court for the District of Columbia.


In 2014, John founded and became the managing partner of his namesake practice, The Law Firm of John P. Mahoney, Esq., Attorneys at Law. Based in Washington, D.C., just steps from the White House, the award-winning firm specializes in federal employment litigation and national security clearance appeals. Known as the “caring federal employment lawyers,” John and the majority of his legal team are former federal employees themselves. (John was appointed to be a statutory member and ultimately became the vice chairman of the U.S. Government Accountability Office’s (GAO) Personnel Appeals Board (PAB), on which he served as an Executive Schedule (ES-IV level) administrative judge).  These top-rated attorneys not only hold an in-depth understanding of federal employment law, but they also stand ready to protect and defend the rights and careers of their clients throughout the world. The team defends clients against allegations of misconduct and prosecutes EEO discrimination and whistleblower retaliation complaints, as well as security clearance appeals, offering not only adept counsel, but fierce advocacy. According to John, it is this dedicated service and incredible talent pool that sets them apart from all other federal employment law firms. And the legal community agrees—as a result of their impressive performance record and overall client satisfaction, the attorneys have received numerous awards. Most recently, they were included in the 2021 Bar Registry of Preeminent Lawyers, named Top Lawyers of Washington D.C. by the Baltimore Sun, and maintain a Superb 10.0 AVVO rating as an AV Preeminent Law Firm on Martindale-AVVO.


John, himself, has also collected quite an inspiring list of honors and awards. He was selected as a 2021 Top-Rated Lawyer in Labor & Employment and as a 2021 Top-Rated D.C. Metro Lawyer in Labor & Employment Law by The National Law Journal, Corporate Counsel Magazine, and American Lawyer Magazine, and Corporate International named John as the 2021 Federal Employment Lawyer of the Year in Washington, D.C. Most recently, he was selected as Washington, D.C’s Leading Employment and Labor Rights Attorney of the Year within Acquisition International (AI) Global Media’s 2021 Leading Advisor Awards.


Prior to and since founding his firm and collecting a bevy of awards, John also served as an expert witness on FEL He has also served as general counsel to various unions, as senior associate to the general counsel of the Senior Executives Association (SEA), outside employment or national security law counsel to multiple federal agencies, private federal contractor companies, and other corporations. John also notes that he has first-hand experience as a federal employee, serving as a manager within a federal agency, as well as a federal agency administrative judge interpreting federal employment and labor law, which is rare within the industry. Because he can offer such a diverse and unique perspective, John is a frequently published author and a regular public speaker and media commentator on federal employment, security clearance, and labor law issues.


John’s connection to labor and employment law began in his childhood. His father was a labor organizer and very active in the Machinists Union in their hometown of Worcester, Massachusetts, so as a child he played on union ballot boxes in his basement. As a young democrat, John’s father also worked on John Kennedy’s presidential campaign in 1959-60, his stories of which led to John’s interest in federal politics (John later was elected president of the Maryland Young Democrats and has worked on several political campaigns himself) and the labor movement. When his father passed away, John was a freshman in college, studying computer science. He recalls, “One of the last things my dad said to me was, ‘I think you’d be a great lawyer.’” John had never considered that career field before then. As fate would have it, sometime later, after transferring his academic focus to business and political science, John was advised by the dean to attend law school in Washington, D.C., which he did. His first job in the legal sector was as a as a law clerk for a federal employment law firm, and, as John says, “The rest is history.”




John P. Mahoney, Esq.

Founding and Managing Partner

The Law Firm of John P. Mahoney, Esq. Attorneys at Law

Ronald Reagan Building and International Trade Center

1300 Pennsylvania Avenue, NW, Suite 700, Washington, D.C. 20004


Twitter:  /  @AttorneyMahoney


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