[2] During the American Civil War, he served as colonel of the 5th Massachusetts Militia Regiment.

After the war he became a Veteran Companion of the Military Order of the Loyal Legion of the United States.

In 1869 he was elected captain of the Ancient and Honorable Artillery Company of Massachusetts.

A highly active Freemason, Lawrence served as Most Worshipful Grand Master of Massachusetts from 1881 to 1883.

From 1909 to 1910, he served as the Sovereign Grand Commander of the Northern Masonic Jurisdiction of the Scottish Rite.