[4] Clery's principal themes included the difficulties of Roman Catholic graduates seeking professional employment, dramatic criticism (he hailed Lady Gregory's play Kincora as the Abbey Theatre's first masterpiece but was repulsed by the works of Synge), Catholic-Protestant rivalry, tension within the Dublin professional class, and the vagaries of the Gaelic revival movement.
[3] Clery advocated partition on the basis of a two nation theory, first advanced in 1904–1905 (possibly in response to William O'Brien's advocacy of securing Home Rule through compromise with moderate Unionists).
Clery was not particularly successful as a barrister, but on the establishment of University College Dublin (UCD) in 1909 he was appointed to the part-time post of Professor of the Law of Property.
[1] He was one of the lawyers who advised Éamon de Valera that the Irish Free State was not legally obliged to pay the Land Annuities which had been agreed in the Anglo-Irish Treaty of 1922.
(Clery also wrote as "Chanel" for the University College paper at St. Stephen's, and as "Arthur Synan" for the New Ireland Review.)