At the Cantonal Council, he was the leader of the Liberal opposition to the Conservative government of Johann Kaspar Bluntschli.

[2] In 1847, Furrer was appointed member of the commission tasked with reaching a peaceful settlement for the Sonderbund War.

After the Federal victory and the end of the civil war, in 1848 he was elected by the canton of Zurich to the Council of States.

For his significant contribution to the drafting of the 1848 constitution, which established Switzerland as a federal state, Furrer was elected President of the Swiss Confederation by the legislature, becoming the head of the newly created executive power of Switzerland, the seven-member Federal Council.

He resolved the question regarding stateless persons, enacted a law in 1850 protecting religiously mixed couples, and founded government agencies responsible for settling conflicts of jurisdiction between the Confederation and the cantons.