Captain Martin Tierney was born in New York. He started his law enforcement career in 1977 as Military Police Officer. Captain Tierney is a veteran of the US Army. He was a paratrooper and the 82nd Airborne Division. He served overseas stationed in Wurzburg, Germany and later at NATO Support Command in Brussels, Belgium.

In 1984 Captain Tierney joined the West Palm Beach Police Department where he served in Patrol, four years later he became a Traffic Homicide Investigation. In 1993, he worked in Dispatch and later as the Court Liaison as well as Coordinator of the Community Service Program for 1st Offenders. He also worked in Planning and Research Accreditation.

In 1998, Captain Tierney was promoted to Sergeant and worked in Road Patrol. In 2001, he became actively involved in Homeland Security issues within the Police Department.

In 2004, he was promoted to Lieutenant and assigned to Patrol as a Shift Commander. Four years later Captain Tierney was transferred to the Staff Services Division.

Captain Tierney received his Associate's Degree as a Legal Assistant in 1995 from Palm Beach Community College. In 2001, he received his Bachelor's Degree from Northwood University in Business Administration. In 2009, he received his Master's Degree in Emergency and Disaster Management from the American Military University. Captain Tierney is also a graduate of the 119th Administrative Officer's Course at the Southern Police Institute, University of Louisville.

Captain Tierney has served 17 years as a Hostage negotiator; he is State and Nationally certified as an Instructor in the National Incident Management System and Incident Command System, as well as a Community Emergency Response Team (CERT) instructor.