Lieutenant Colonel Keefer entered the Marine Corps in February 2003 during his sophomore year of college.  He later finished his Bachelor’s degree at Birmingham-Southern College in May 2005, and was commissioned a Second Lieutenant.    

Lieutenant Colonel Keefer's deployments include: Haditha, Iraq (February - November 2007) with 1st Battalion, Third Marines as the Scout Sniper Platoon Commander; Karmah, Iraq (July 2008-February 2009) with 1st Battalion, Third Marines as the Task Force Intelligence Officer; Europe and Africa with Special Purpose MAGTF - Crisis Response (October 2013-January 2014) as the MAGTF Intelligence Officer; Central Command with 24 MEU (December 2014 - July 2015) as the Assistant MAGTF Intelligence Officer and Joint Combined Planning Cell J-2 Operations Officer; and Naples, Italy (June-October 2022) Sixth Fleet Headquarters with 2d Marine Expeditionary Brigade as the Assistant Chief of Staff N-2 for Task Force 61/2.

Lieutenant Colonel Keefer is a graduate of the Infantry Officer Course (2006), Ground Intelligence Officer Course (2006), Scout Sniper Platoon Commander Course (2006), and Weapons and Tactics Instructor Course (2013).  He is a Distinguished Graduate of resident Expeditionary Warfare School (2012-2013), MAGTF Intelligence Officer Course (2013), and resident Command and Staff College (2016-2017).  He completed his Master of Military Studies degree at Marine Corps University in June 2017.

Lieutenant Colonel Keefer reported to 3d Radio Battalion, III MEF Information Group, III MEF in June 2023, and took command on 15 June 2023. 

Lieutenant Colonel Keefer's personal decorations include the Navy and Marine Corps Achievement Medal, Navy and Marine Corps Commendation Medal (Three Gold Stars), and Meritorious Service Medal (One Gold Star).  

Lieutenant Colonel Keefer is married to the former Blythe Myers of Marietta, GA and they have three kids: Jackson (10), Annie (8), and Levi (4).