Derek A. Cohen


215 825 5282

212 335 2049

Derek is a highly decorated former federal prosecutor and seasoned trial lawyer who has been described as a “go-to defense expert for clients involved in high-profile criminal proceedings, drawing on experience in areas such as allegations of insider trading and corruption” according to Chambers USA: America’s Leading Lawyers for Business. Derek regularly represents U.S. and foreign companies and individuals in a wide range of criminal and regulatory investigations by federal, state and local authorities, including, among others, allegations of healthcare fraud, securities fraud, tax fraud, bribery, False Claims Act, sanctions/export violations, product recalls, antitrust, and Foreign Corrupt Practices Act (FCPA) violations. He also has significant experience in complex commercial litigation matters and internal investigations.

Clients benefit from Derek’s extensive prior prosecutorial experience. He served in the Criminal Division of the U.S. Department of Justice, where he was Deputy Chief of the Division’s Fraud Section as well as Deputy Director of the Deepwater Horizon Task Force. Derek also previously served as an Assistant U.S. Attorney with the U.S. Attorney’s Office in Philadelphia, where he prosecuted some of the office’s most significant white collar matters. Derek received the highest awards bestowed by the Department of Justice and the Federal Bureau of Investigation for his role in helping lead the criminal investigation into the Deepwater Horizon oil spill, which resulted in the largest criminal resolution in U.S. history. Derek began his career as an Assistant District Attorney in Manhattan under the Hon. Robert M. Morgenthau.

Derek is a highly regarded trial attorney. According to Chambers, he is “a master in front of juries,” and is “extraordinarily savvy and very skilled.” Market sources also noted to Chambers that they “would not want to try a case against him.” Derek has twice been named “Litigator of the Week” by American Lawyer for his successful trial defense of an investment analyst charged with insider trading in the Central District of California and his False Claims Act verdict against Eli Lilly in the Northern District of Illinois. He has previously taught Trial Advocacy at Temple Law School and has also guest lectured at Harvard and Penn Law Schools in the area of white collar crime.

Prior to joining Walden Macht Haran & Williams, Derek was a partner for nearly 8 years at a major international AmLaw 50 law firm.

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Derek has consistently obtained favorable outcomes for his clients in a wide range of investigations and litigations. Some examples include:

Obtained a jury verdict against Eli Lilly for over $200 million in a False Claims Act trial in the Northern District of Illinois

The successful defense at trial of former J.P. Morgan Securities LLC analyst Ashish Aggarwal on conspiracy, insider trading, and wire fraud charges. A Central District of California jury found Aggarwal not guilty related to his role in an alleged insider trading scheme. This was a rare defense victory in an insider trading case and the first since the December 2016 U.S. Supreme Court decision in Salman v. United States lowered the bar for prosecutors in insider trading cases.

Securing a deferred prosecution agreement for a publicly traded transportation company in connection with an investigation into accounting and securities fraud by the U.S. Department of Justice and the SEC.

Obtaining a non-jail sentence for an individual convicted in the Southern District of New York with FCPA violations for bribing the former President of the United Nations General Assembly.

Avoiding charges for a Fortune 500 company under investigation for potential environmental crimes by Federal and State authorities.

Avoiding charges for a London-based bond trader in a criminal antitrust investigation by the U.S. Department of Justice.

Avoiding charges for a publicly-traded biotech company under criminal investigation by the DOJ for alleged trade secret theft.

Avoiding charges for employees of a major automobile parts manufacturer under criminal investigation in connection with a product recall.


Derek is widely recognized as a leading white collar criminal defense lawyer by a number of prestigious legal publications, including Chambers USA: America’s Leading Lawyers for Business, Lawdragon 500 Leading Litigators in America, Benchmark Litigation, Euromoney’s Expert Guides: White Collar Crime Lawyers, The Legal 500, and Global Investigations Review 100.

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Derek has been an active participant in bar association activities throughout his career, including serving as co-chair of the ABA White Collar Young Lawyers Subcommittee for the New York region and as secretary of the Criminal Courts Committee, and as a member of the Criminal Advocacy Committee of the Association of the Bar of the City of New York. He is also a member of the Federal Bar Council and the New York Council of Defense Lawyers, a membership by invitation to a group of top criminal defense practitioners. Derek has also served as a member of the Criminal Justice Act Panel for the Southern District of New York.

Derek is a member of the UJA/Criminal Law Committee as well as alumni groups for the Manhattan DA’s Office and the U.S. Attorney’s Office for the Eastern District of Pennsylvania.