It was taken to England hidden in the sole of a shoe by E. W. Perera. As a result of this the governor Sir Robert Chalmers was recalled. In 1920 Peiris was elected President of the Ceylon National Congress staunchly supported by D.S. Senanayake and F.R. Senanayake. Forming the Congress was a self-sacrificing effort by Peiris and the National Association, up until that time the most powerful lobby in Ceylon. He continued the struggle for reforms and promoted greater representation of natives in the government bureaucracy and the judiciary. He also campaigned to abolish the poll tax. There was wide support for Peiris' nomination to the Legislative Council of Ceylon. On two occasions when nominations had to be made for the position of ""an educated Ceylonese"" James Peiris was passed over, notwithstanding his ability and integrity. Peiris also was opposed to the principle of nomination. Immediately the elective principle was introduced into the Legislative Council, Peiris was elected unopposed. At the same election his brother-in-law Sir Henry De Mel was also elected unopposed, on behalf of the Low Country Products Association. In 1922 Peiris led the fight against the Supply Bill which sought to increase taxation and led a walkout from the Legislative Council in protest. In 1924 the legislative council was reconstituted with a majority of elected representatives. Peiris was elected as Vice-President – a position he held until his death in 1930. The post of President was held nominally by the Governor and Peiris presided over the Council and acted as Officer Administering the Government. Peiris accepted in 1925 a knighthood from the King and was a Justice of the Peace for the whole island. He was the first Ceylonese occupant of Queens House as Acting-Governor. Peiris was first to propose the creation of a University College in Colombo and the means of financing it. Following the establishment of the University College, Colombo (later to become the University of Ceylon), Peiris was a Member of the Advisory Council of the new University College. In 1889, Peiris married Grace de Mel, daughter of Jacob De Mel (1839-1919) and Dona Helena née Ferdinando (1850-1906) and had two sons and two daughters; Ethel, Louise, Leonard and Devar Suriya Sena. His nephews were artist Harold Peiris and Bishop Lakdasa De Mel. He was a devoted Christian and a standing committee member of the Church of England synod.