Career
Mansfield"s father was a tenant farmer who was evicted. He was president of the Irish National Teachers" Organisation (INTO) in 1910-1911, and later its first full-time general secretary. He was dismissed as principal in October 1912 after his 1911 INTO president"s address criticised West. H. Welpy, a school inspector who was reputed to give poor assessments to keep salaries down.
He was later Chairman of the Wages Board c.1921.
With Labour Party support, Mansfield was elected in 23rd place, thereby securing a three-year term to expire at the 1925 election. The Irish Civil War was in progress, and the same day, two pro-Treaty TDs were shot, one fatally.
The following day, four imprisoned anti-Treaty leaders were executed in reprisal. On 12 December, Mansfield sent a telegram resigning from the Seanad "on account of Friday"s reprisal" and stating that "peace is Ireland"s only hope".
Ernest Blythe suggested later that Mansfield had resigned in panic at anti-Treaty commander Liam Lynch"s order to assassinate all Senators.
He was a lay commissioner on the Appeals Tribunal of the Irish Land Commission from 1934 to 1950. When Kathleen Browne complained in the Seanad about his appointment, his expertise and impartiality were commended by minister Joseph Connolly and senators Michael Comyn, James Charles Dowdall, and William Cummins. As commissioner, he was an influential advocate of land division, and the rights of evicted tenants.