Before joining Barnes & Thornburg, Nick was an attorney advisor in the Regulations and Rulings Directorate of CBP's Office of Trade. In the Commercial Trade Facilitation Division, he wrote and published binding rulings on various entry issues, the valuation of merchandise, and the classification of goods under the Harmonized Tariff Schedule of the United States (HTSUS), including the additional provisions of Chapter 99. He also certified the application of additional duties under Sections 201, 232, and 301 and the International Emergency Economic Powers Act (IEEPA), made decisions on country of origin, addressed protests filed by importers, and supported the government's position in litigation, often serving as a Rule 30(b)(6) witness.

In CBP's Regulations and Disclosure Law Division, Nick drafted and published regulations in the Federal Register, including rules governing the importation of cultural property, the implementation of the Automated Commercial Environment (ACE), and continuing education requirements for licensed customs brokers. He responded to public comments, advised government offices on statutes and regulations, and analyzed and updated tariff shift rules. He also trained new attorneys, government officials, and members of the public on tariffs, additional duties, the entry process, and Administrative Procedure Act (APA) requirements.

Earlier in his career, Nick spent three years at a Washington, D.C., government affairs firm, where he helped clients develop government affairs strategies and build relationships with federal agencies, congressional offices, and White House staff. During law school, he represented clients as a student attorney in Boston College's Civil Litigation Clinic and gained additional experience as an extern with the Massachusetts Office of the Attorney General, an intern with the Massachusetts Department of Professional Licensure, and an intern in the Civil Division of the U.S. Attorney's Office in Washington, D.C.