Bernard Byrne was born in the townland of Kilmore, County Roscommon, in July 1861. On the 22nd February 1881, at the age of 19, he was appointed to the Royal Irish Constabulary. He was 5'9¼" tall and was previously employed as a farmer. Upon completion of training, Constable Byrne, 46666, was allocated to Cork East Riding, where he was stationed at Mallow. He was later transferred into Cork City, and married Kate Donovan in the Church of St Francis, Cork City, on the 14th April 1894. He was then transferred to Queenstown (Cobh), where he spent all his service as a detective.
On the 1st December 1899 he was promoted to Acting Sergeant, and to Sergeant on the 1st February 1902. During his service up to 1911 he received 9 favourable commendations. He was awarded the K.P.M. (King's Police Medal) for distinguished service by King George V in 1911 — the only detective to receive such an award.
On the 21st July 1903 Sergeant Byrne was promoted to Head Constable, a rank he held until his retirement on the 1st April 1920.
Bernard “Barney” Byrne died on the 30th August 1949 and was buried at Glasnevin Cemetery, Dublin.