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Professional portrait of Daniel J. Vaccaro

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Clients turn to Dan when facing governmental investigations, enforcement actions or complex civil litigation, relying on him for the judgment, sound counsel, and strong courtroom skills he has developed through years of trial experience as a federal and state prosecutor and defense lawyer.

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Dan routinely helps companies and individuals respond effectively to government inquiries, investigations, prosecutions or enforcement matters. He represents targets, defendants, and witnesses at all stages of the criminal process, including grand jury investigations, plea negotiations, trials, and parallel civil enforcement proceedings. Dan has defended clients in SEC, FERC, EPA, antitrust, CFTC and related State enforcement investigations and actions. He has successfully represented clients in matters involving alleged financial services fraud, securities fraud, healthcare fraud, commodities fraud, pandemic relief fraud, defense contracting, export violations, environmental violations, employer-based immigration violations, trade secrets, money-laundering violations, antitrust violations, False Claims Act, and Foreign Corrupt Practices Act violations.

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Dan also helps corporate organizations structure and conduct internal investigations of alleged illegal or unethical activity. He has handled investigations for both public and private entities in a wide range of industries, including financial services, energy, manufacturing, agricultural, education, non-profits, staffing, trucking, and defense contracting. In addition, he provides counsel to business organizations to develop guidelines and improve corporate compliance programs to avoid intervention by federal and state investigators.

On the civil side, Dan has prosecuted and defended a wide variety of complex claims. He concentrates on large-scale commercial disputes, contract matters, post-closing acquisition disputes and other business tort cases.

Dan has conducted more than 135 jury and bench trials before federal and state courts, has represented clients in numerous administrative and regulatory hearings before state and local agencies, and lead many arbitration hearings. He has also successfully litigated and argued before the U.S. Court of Appeals for the First and Seventh Circuits.

Dan is the Chair of the Firm’s Litigation Practice Group, having also led the group from 2012-2017.

As a current and former firm leader, Dan also professionally coaches business executives and attorneys on a variety of topics, including career development, leadership, business development, work/life balance, and successful interpersonal communication strategies.

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Defending Against White-Collar Charges and Government Investigations

Dan has successfully represented clients in a wide variety of criminal cases and investigations in recent years. Among these many representations, he successfully:

Defended a publicly-traded financial institution in a multi-year SEC enforcement investigation and parallel grand jury investigation involving allegations of financial fraud that resulted in no finding of liability or financial penalty to financial institution

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Defended farm labor contracting organization in federal criminal investigation related to H-2A visa program

Defended a variety of business entities from multiple industries in False Claims Act investigations under the Paycheck Protection Program and other COVID related programs

Defended university hospital system in False Claims Act investigation related to Medicare and Medicaid reimbursement for cancer related healthcare services

Defended alcohol beverage distributor in regulatory and criminal enforcement case related to alleged violations of State alcoholic beverage control statutes in implementing regulations.

Defended biosciences start-up in United States Department of Army criminal investigative procurement fraud investigation alleging fraud related to the Department of Defense’s small business innovation research grant program.

Defended a higher education institution in False Claims Act investigation related to use of federal grant funds

Defended a dairy producer in federal immigration investigation related to worker documentation and various visa programs

Defended manufacturer of scientific testing equipment in U.S. Department of Commerce investigation related to export activities

Represented energy trading company in grand jury investigation related to commodities fraud conspiracy

Defended management employee in SEC investigation of alleged insider trading violations

Represented national advocacy organization in John Doe investigation related to campaign finance activities

Defended addiction treatment provider in DEA civil enforcement action

Defended an industrial refrigeration service corporation in a criminal trade-secret prosecution

Represented a pharmaceutical distributor in a grand jury investigation related to Medicaid fraud

Defended an agricultural manufacturer in an investigation involving a death of a third party by employee operating agricultural equipment

Defended agricultural insurance agency in grand jury investigation related to insurance fraud in agricultural sector

Defended securities broker dealer in stock manipulation securities fraud investigation

Represented former school board director in relation to investigation involving allegations of teacher misconduct with students

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Leading Internal Investigations of Alleged Wrongdoing

Dan has conducted numerous internal investigations. Recently, he:

Conducted internal investigation of state contracted welfare agency related to administration of COVID related cash assistance program using emergency funding allocated to the state through the American Rescue Plan Act (ARPA) of 2021

Conducted internal investigation of actions by management level employees at solid waste disposal facilities related to compliance with federal and state environmental clean air and clean water regulations

Conducted internal investigation of actions of former employees of higher education organization related to use of federal student loan funds

Conducted internal investigation of actions of former CFO at university related to compliance with federal education regulations

Conducted internal investigation of actions of employees engaged in an internal fraud and theft scheme against manufacturing facility

Conducted internal investigation of actions of educator related to historical allegations of inappropriate conduct with students

Counseling on Compliance

Given his previous prosecution experience, Dan is often called upon to develop internal compliance, policies and procedures for clients to comply with various federal and state laws. Dan has prepared compliance programs such as the following:

Created anti-money laundering compliance program related to pre-paid credit cards for national retailer

Created Foreign Corrupt Practices Act compliance and training program for international entertainment and hospitality company

Created numerous compliance programs related to interaction with federal and state law enforcement for a variety of employers

Prevailing in Complex Civil Cases

Acted as lead counsel for all trial and appellate litigation involving a correspondent banking agreement resulting in a $53 million judgment for client

Represented international manufacturer of beverage equipment in arbitration alleging defect in product resulting in dismissal of all claims against manufacturer

Represented an insurance-processing and technology company in a dispute against former officers who left the company to begin a competing enterprise

Defended a leading manufacturer of street-sweeper equipment in a products liability action

Defended an international travel service company in a negligence action arising out of bus accident involving U.S. tourists traveling abroad

Defended financial institution against liability claims arising from criminal actions by third party against institution customer

Defended pharmaceutical manufacturer in arbitration against claims by former CEO related to stock warrants

Represented financial institution services provider in coverage action against primary and excess insurance policy issuers for losses related to product

Winning Cases — and Recognition — as a Federal Prosecutor

As an Assistant U.S. Attorney in the U.S. Attorney's Office for the District of Puerto Rico, Dan was responsible for investigating and prosecuting organized crime, capital murder, international narcotics, money laundering, law enforcement corruption, white collar, and other major felony cases. During his service as a federal prosecutor, he:

Received the U.S. Department of Justice’s Director’s Award for Superior Performance from the U.S. Attorney General

Received a Special Achievement Award from the U.S. Department of Justice for the investigation and prosecution of a former state prosecutor who was involved in a conspiracy with a violent drug trafficking organization

Received an award from the U.S. Department of Treasury, U.S. Customs Service — Office of Internal Affairs for his work on law enforcement corruption cases

Received an award from the U.S. Department of Veteran Affairs — Office of Inspector General for the investigation and prosecution of a violent criminal organization responsible for the murder of a federal police officer for the U.S. Department of Veteran’s Affairs

Served as attorney coordinator for the Puerto Rico–U.S. Virgin Islands High Intensity Drug Trafficking Area (HIDTA) program, which was voted “Outstanding HIDTA in the Nation” in 2002, during his tenure

Taking on Big, Multi-Party Litigation as a State Prosecutor

As an Assistant State’s Attorney in Howard County, Maryland, Dan prosecuted misdemeanor and felony cases. His work preparing, directing and trying multi-party complex litigation included investigating and prosecuting Howard County’s first organized gang case.

Daniel J. Vaccaro

My Why

What powers my practice

Credentials

Engagement

Insights

Michael Best Welcomes AJ Bianchi, Jr. as Senior Counsel to Litigation Team in Madison Office

Benchmark Litigation Recognizes Michael Best Attorneys as 2026 Litigation Stars

Michael Best Attorneys Earn Recognition in The Best Lawyers in America 2026 List

My Why

What powers my practice

Credentials

Practices

Education

Admissions

Honors & Recognition

Engagement

Professional

Insights

Michael Best Welcomes AJ Bianchi, Jr. as Senior Counsel to Litigation Team in Madison Office

Benchmark Litigation Recognizes Michael Best Attorneys as 2026 Litigation Stars

Michael Best Attorneys Earn Recognition in The Best Lawyers in America 2026 List

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