Religious liberty, church and state, law of remedies, constitutional law
- Served as lead counsel in numerous cases in the courts, including six in the Supreme Court, most recently Holt v. Hobbs, Town of Greece v. Galloway and Hosanna-Tabor Evangelical Lutheran Church and School v. Equal Employment Opportunity Commission
- Fellow of the American Academy of Arts & Sciences and vice president of the American Law Institute
- Laycock is in the process of publishing a five-volume collection of writings on religious liberty. (Story)
Labor and sports law; health law
- Served as an appellate branch attorney in the Office of the General Counsel of the National Labor Relations Board
- Practiced labor law at O'Donoghue & O'Donoghue in Washington, D.C.
- Was editor-in-chief of the "Railway Labor Act Treatise" for the American Bar Association's labor and employment law section. He also served as secretary of that section in 1987-88.
Environmental law and climate change, administrative law
- Clerked for Judge Harry T. Edwards on the U.S. Court of Appeals for the D.C. Circuit
- Founding executive director of the Institute for Policy Integrity at New York University School of Law
- Co-authored "Retaking Rationality: How Cost-Benefit Analysis Can Better Protect the Environment and Our Health." The book became the foundation for a new approach public interest organizations could take in arguing for policies to protect the environment. (Faculty Q&A on related scholarship)