[2] Charles Flandin supported the Republican opposition during the Second French Empire and became vice-president of the General Council of Yonne.

[3] On 20 January 1908 Flandin proposed a revision of "the penal laws concerning vagrancy and begging, the organization of assistance through work and the supervision of nomads exercising itinerant professions."

These included committees on the colonial customs regime, economic blockade of Germany, and offenses against the external security of France.

He gave numerous speeches on subjects such as extradition between France and Britain, voting secrecy and wards of the nation.

[3] In the legislative elections of 1914 Flandin gave his support to Paul Bluysen as deputy for French India.

Flandin pointed out that the high rates of acquittal in 1914 and 1915 were probably due to reluctance of judges to apply such a severe sentence.

[7] On 29 March 1918, during a difficult phase of the war, the Senate decided to review a proposed change to the code of military justice of 3 October 1916.

As rapporteur, Flandin stated that this was not the time to reopen the question, and that the need for discipline must be addressed as well as the demand for justice that had been formulated by the Chamber a few months earlier.

[8] The senators followed Flandin in agreeing on the principle of a secret ballot and the freedom of the accused to communication with his defense council, but refused to increase the number of judges on the tribunals from five to seven.

As president of the Committee on Foreign Affairs Flandin warned Aristide Briand in September 1916 that, "Our enemies could not find a subject more likely to overexcite Muslim fanaticism.

[9] In 1917 Flandin criticized conscription of Algerian troops, since it thought it wrong to force the indigenous people to accept French practices and ideals.