On 2 November 1910 the cabinet was dissolved and Chéron left the government. He joined the radical left, and presented five bills on social issues. He was chosen to report on many financial projects, and to present the general report on the budget in 1911, 1912 and 1913. On 23 January 1913 he presented and defended a vote of confidence in the Briand government. Chéron was an honorary president of the French consultative committee to the first International Eugenics Conference in London in 1912. On 22 March 1913 Louis Barthou appointed Chéron Minister of Labor and Social Security ("Ministre du Travail et de la Prévoyance sociale"). Chéron appointed a commission to prepare a law on regulating savings companies to protect small savers. He also tried to apply the law on workers' pensions. He left office when the Barthou cabinet fell on 9 December 1913. Chéron was elected to the Senate on 20 July 1913. He was reelected to the Senate on 9 January 1921 and on 20 October 1929. He remained a Senator until his death in 1936. He was actively interested in social issues, but was primarily involved in financial issues. During World War I (1914–18) he worked hard for the war effort. He submitted many legal texts on ways to ensure that as many men as possible were available to the army. On 23 December 1916 he led the Senate to adopt a motion letting the Briand government place the entire war effort under one organization. He also submitted proposals to reduce the social costs of the war, on topics such as rents, leases and taxation of food. One of his proposals significantly extended the role of trade unions. After the war there was a widespread feeling that France must produce more children to make up for the wartime losses. A law against propaganda for abortion and contraception was proposed in January 1919. It included an article that required doctors to give information about abortionists even if they had obtained the information under professional secrecy. As a lawyer, Chéron considered that principle of confidentiality was "the safeguard of his profession." He hastened to clarify that confidentiality was "enacted not in the interests of a profession, but in that of the public order and individual security". He granted that women made all decisions about family planning, and said that propaganda for abortion and contraception "consists in saying to French women: 'You will no longer have children. However, Chéron said Malthusian propaganda was "against the very existence of the country ... this is a question of life or death for France."