James Patrick Anderton (born James Patrick Byrne; 21 January 1938 – 7 January 2018) was a New Zealand politician who led a succession of left-wing parties after leaving the Labour Party in 1989.
Anderton's political career began when he was elected to the Manukau City Council in 1965. In 1984, Anderton successfully stood as the Labour candidate for Sydenham in Christchurch. However, he soon came into conflict with the party's leadership, and became an outspoken critic of the Fourth Labour Government's free-market reforms, called Rogernomics. In April 1989, believing that Labour was beyond change, Anderton resigned from the party.
As Leader of the Alliance and later the Progressive Party, he served as Deputy Prime Minister in the Fifth Labour Government from 1999 to 2002. In 2010, he ran unsuccessfully for the mayoralty of Christchurch. Anderton retired from Parliament at the 2011 election. After his retirement, he and former MP Philip Burdon were the two prominent campaigners for the restoration of ChristChurch Cathedral.
He is also known as James Patrick Anderton.
Anderton died in Christchurch on 7 January 2018, two weeks before his 80th birthday. He was buried at Onetangi Cemetery on Waiheke Island.