John Lawrence was born on January 22, 1938, in Farmington, New Hampshire. He was commissioned a 2LT of Artillery through the U.S. Military Academy at West Point, New York, on June 7, 1961. After completing the Artillery Officers Basic Course and the Hawk Missile System Officer Course, he was assigned to a Hawk Missile Battery in Panama from April 1962 to March 1965. Lawrence attended the Artillery Officer Career Course at Fort Sill, Oklahoma, from April to October 1965, and then served with the 1st Training Brigade at Fort Bliss, Texas, from October 1965 to August 1966, when he left for service in Southeast Asia. Capt Lawrence served with the 1st Infantry Division Artillery in the Republic of Vietnam from September 1966 to September 1967. His next assignment was as an instructor with the Army ROTC detachment at the University of Florida, where he served from October 1967 to June 1970, when he began training for his second tour in Vietnam. Maj Lawrence was assigned to Military Assistance Command Vietnam's Advisory Team 91 in November 1970, and he was killed in action on September 16, 1971. He was posthumously promoted to Lieutenant Colonel and awarded a second Silver Star.

The General Orders for his 2nd Silver Star Citation reads:

For gallantry in action: Major Lawrence distinguished himself by gallantry in action on 16 September 1971 while serving as District Senior Advisor, Tri Tam District, Binh Duong Province, Republic of Vietnam. On this date, Major Lawrence, upon receiving news that the District S1 Officer and five other personnel had been ambushed and killed by an approximate company size North Vietnamese Army Unit, led a reaction force consisting of the 108th Popular Forces Platoon, the 46th Popular Forces Platoon, the District Intelligence Squad, one platoon from the 396th Regional Forces Company and a National Police Team. Upon reaching the location of the first ambush, the force led by Major Lawrence was engaged by the enemy and received severe mortar, rocket, automatic weapons and small arms fire. While leading the reaction force and directing their deployment in action, Major Lawrence killed at least two enemy soldiers before being killed himself. Following his valiant and courageous example, the surviving members of the reaction force, despite their decided tactical disadvantage, ultimately broke the enemy defenses and destroyed their positions. Major Lawrence's conspicuous gallantry in action was in keeping with the highest traditions of the United States Army and reflected great credit upon himself and the military service.