Matthew McMannus was born on May 3, 1895 in Newark, New Jersey and resided in Morristown. He graduated from St. James High School in Newark. Prior to enlisting in the New Jersey State Police, he worked as a mechanic and a pipe-fitter. From September 1917 to April 1918, he served in the United States Army First Air Service Regiment.

He enlisted in the New Jersey State Police on April 1, 1922 as a member of the 2nd Class and was stationed at Troop “B”, Netcong at the time of his death. His service with the New Jersey State Police was characterized by loyalty, fearless performance of duty and faithful and energetic devotion to the high principals of the New Jersey State Police.

Trooper McManus died as the result of injuries received in a motorcycle accident in the line of duty.

He returned to duty in 1923, but was frequently hospitalized due to the injuries he had received. On April 1, 1927 he was placed on a Disablilty Pension. On February 28, 1938, Trooper McManus died.

He served 5 years with the New Jersey State Police and was survived by his wife and two children – a daughter aged 12 and a 5 year old son. Trooper McManus was 43 years old.