Attorney Keily obtained his law degree with Cum Laude honors from the University of Bridgeport School of Law (now known as Quinnipiac Law School) in 1986, where he was a member of the Law Review, a recipient of the Fannie Glickenstein Memorial Scholarship and of the Outstanding Legal Scholarship Award.

Following law school, he served as a part-time associate with the Law Offices of Beck & Edgerhill in Manchester, CT (1986) and was an associate in General Practice with the Law Offices of F. Timothy McNamara in Hartford, CT (1986-1987). In 1988 and 1989, he maintained his own practice in Hartford. In 1989, he became a partner in the firm of Mulholland & Keily. Since 1993, he has maintained his own practice in West Hartford.

He is a member of the Connecticut Bar Association and is licensed to practice in all state courts and the Federal District Court.