Ryan Lee O'Neill


Ryan O’Neill is a Partner in Riker Danzig’s White Collar Criminal Defense and Investigations Group. Her practice focuses on criminal defense, corporate and government investigations, state administrative proceedings, and complex civil litigation.

Ryan rejoined the Firm in 2022 after serving as an Assistant U.S. Attorney for the District of New Jersey, Criminal Division, where she supervised complex criminal prosecutions and civil enforcement actions involving a range of matters, including large-scale healthcare fraud schemes, corporate misconduct, tax, civil, and regulatory offenses, and qui tam whistleblower actions. Ryan most recently served in the Office’s Healthcare Fraud Unit. Her prior positions included roles in the Office’s Opioids Abuse Prevention & Enforcement Unit and the Public Protection Unit, where she handled cases involving drug diversion, violent crimes, and child sex offenses.  Her notable achievements include:

  • Securing multiple convictions and over $100 million in criminal proceeds flowing from a national syndicate of individuals purchasing and selling physicians’ orders for durable medical equipment, genetic testing, and compounded medications—one of the largest healthcare fraud conspiracies ever investigated by the Department.
  • Securing the conviction of a detective sergeant of the N.J. State Police for tax fraud and witness tampering.
  • Securing multiple convictions and millions of dollars in criminal proceeds flowing from an international insurance fraud and money laundering scheme.
  • Securing the conviction of an individual who falsely procured dozens of HB1 visas enabling temporary employment status for non-citizens at large banks through the United States.

Results may vary depending on your particular facts and legal circumstances.

Ryan also has prior defense experience in a broad range of civil and white collar criminal cases, including state and federal grand jury investigations, state professional and licensing board inquiries, multi-district products litigation, and state consumer class actions.

Ryan received her J.D. degree, cum laude, from Seton Hall University School of Law in 2010, where she was a publishing member of the Seton Hall Circuit Review and a member of the Interscholastic Moot Court Board.  She received a B.S. in Business Management from The Richard Stockton College of New Jersey in 2007.  Ryan was an associate with Riker Danzig for four years before serving in the U.S. Attorney’s Office.  While at the Office, she was awarded the New AUSA and served as a Special Emphasis Program Manager for the Federal Women’s Program.  Previously, she was an associate and summer associate with Pepper Hamilton LLP.  Ryan is admitted to practice in New Jersey.

Areas of Emphasis

Complex Civil Litigation

Bar Admissions

New Jersey

United States District Court, District of New Jersey


Seton Hall University School of Law, J.D., cum laude, 2010

The Richard Stockton College of New Jersey, B.S., 2007

Professional Activities

Member, New Jersey Board of Bar Examiners’ Committee on Character

Rankings & Recognitions

In 2022, Ryan was named a “New Leader of the Bar” by the New Jersey Law Journal. A high honor, the Law Journal selects for this recognition attorneys in their second decade of practice whose achievements in the workplace and public service involvement distinguish them from their peers.

Ryan has been included in The Best Lawyers in America®, a peer review of U.S. lawyers, in the Criminal Defense: White Collar Law field for 2024.

See Awards and Honors Methodology.

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