Colonel Fallon was commissioned as a Second Lieutenant following graduation from Boston College in 1994. Upon graduation from The Basic School and the Infantry Officers Course, Colonel Fallon reported to 3d Battalion, 8th Marines and served in the billets of platoon commander, company executive officer, assistant operations officer and deployed to Liberia, Japan, and Panama.
In 1998, Colonel Fallon returned to The Basic School to serve as a staff platoon commander for three Basic Officer Classes and one Warrant Officer Basic Course. Following this tour, he attended the Amphibious Warfare School.
From 2002 to 2004, Colonel Fallon was the Weapons Company Commander, 1st Battalion, 8th Marines and deployed with the 26th Marine Expeditionary Unit in support of Operation Iraqi Freedom. In 2004, he transferred to 8th Marine Regiment and deployed to Haiti in support of Operation Secure Tomorrow.
Colonel Fallon was selected to participate in the Leadership and Education Development Program through the United States Naval Academy Naval Postgraduate School in 2004 where he earned a Master’s of Science degree in Leadership and Human Resources. He remained at the Naval Academy until 2007 to serve as a Company Officer and Officer Representative for the Naval Academy Wrestling Team.
From 2007 to 2010, Colonel Fallon served as the Commanding Officer, Recruiting Station Charleston.
Colonel Fallon served as the Ground Operations Officer, II Marine Expeditionary Force in 2010. From 2011 to 2013 he was the Inspector-Instructor, 1st Battalion, 25th Marines at Fort Devens, Massachusetts and deployed in support of Operation Enduring Freedom.
From 2013 to 2016 Colonel Fallon served as the Executive Officer, 2d Marine Regiment and deployed to Afghanistan in support of Operation Enduring
Freedom and later to Spain with the Command Element of the Special Purpose Marine Air Ground Task Force Crisis Response Africa. During that second deployment he assumed command of 2d Battalion, 8th Marines at Mihail Kogălniceanu Airbase, Romania.
Colonel Fallon attended the Naval War College from 2016 to 2017 and earned a Master’s of Arts degree in National Security Strategy. In 2017 Colonel Fallon assumed command of the 9th Marine Corps District.
Colonel Fallon’s awards include the Meritorious Service Medal with two gold stars, the Navy and Marine Corps Commendation Medal with combat distinguishing device and three gold stars, the Navy and Marine Corps Achievement medal, and the Combat Action Ribbon.