After being demobilised in January 1946, he returned to practising law, and joined the newly formed Liberal Party. On 17 December 1949 he was elected to the Victorian Legislative Assembly for Kew, a safe conservative seat in Melbourne's eastern suburbs. The sitting member, Wilfrid Kent Hughes, had moved up to federal politics. Rylah would hold this seat without serious difficulty until resigning in March 1971. Rylah's political colleagues quickly recognised his talents, and in 1953 he was appointed deputy leader of the party under party leader Henry Bolte, a post he would hold for 18 years. Following the Victorian election of 1955, the Liberal Party gained office. Accordingly, on 7 June 1955, Rylah was appointed Deputy Premier and Chief Secretary of Victoria, as well as Government Leader in the Legislative Assembly. Described as a "human dynamo", Rylah had great capacity for work. During his time as Chief Secretary he oversaw the consolidation of all Victoria's statutes, introduced legal off-course betting using the New Zealand Totalisator Agency Board as a model, allowed cinemas to open on Sundays, did away with six o'clock closing of hotels, thereby permitting alcohol to be served till 10pm, allowed sport to be played on Sundays, and sponsored legislation for compulsory wearing of seat-belts for motorists and to provide for random breath-testing of drivers. As attorney general he also approved Australia's last execution with the execution of Ronald Ryan in 1967. In something of a contrast to this dynamism, Rylah's attitudes regarding morality and censorship were seen by many to be reactionary and repressive. His remark in 1964 that he would not allow his 'teenage daughter' to read Mary McCarthy's novel The Group became notorious. When it was pointed out to him that he did not have a teenage daughter, he replied that he could always imagine one. He zealously took on the role of public censor, banning everything from James Joyce's Ulysses to Rudyard Kipling's Barrack-Room Ballads. He was also responsible for prohibiting performances of the play The Boys in the Band and for the covering of public statues of Michelangelo's David. He separated from his wife Ann in 1968, and on 15 March 1969 she was found dead in her garden. An autopsy determined that she had died of a stroke and the state coroner, in an unusual move which generated considerable controversy at the time, allowed her remains to be cremated without an inquest into her sudden death. Within seven months Rylah married Norma Alison Reiner, née French, a divorcee 17 years his junior. Reiner had four children to three fathers: Ace Phillips, David and Sam Reiner, and Michael Clark. Clark's existence was a family secret until after Reiner's death, when he was contacted by David Reiner. In the late 1960s Dr Bertram Wainer began a campaign to reform Victoria's anti-abortion laws, claiming they promoted misery, graft and corruption. Rylah refused to deal with him. Both Rylah and Bolte were reluctant to antagonise the Catholic-dominated Democratic Labor Party, on whose support the government relied, but came under increasing pressure from the media and the Liberal Party's State council to review the matter. In January 1970 William Kaye, Q.C. was appointed by the government to inquire into Wainer's allegations. His report that year led to the prosecution and gaoling of a number of police officers. The East Kew branch of the Liberal Party showed its dissatisfaction with Rylah's handling of the abortion controversy by challenging his endorsement for the next election. In February 1971 Rylah announced that he would resign from parliament in the following month. However he collapsed at his desk on 5 March and spent the next four months in hospital. He was succeeded as member for Kew and deputy premier by future premier Dick Hamer. He retired to his rural property, pursued his interest in horse-racing, and became a director of several companies. He died on 20 September 1974 in hospital in the Melbourne suburb of Fitzroy, survived by his second wife, and by the children of his first marriage. Rylah had a state funeral.
