She was a member of the Labour Party until her resignation in October 2019.Ellman was elected as a councillor on the Lancashire County Council in 1970, becoming the Labour group leader in 1977 and leader of the council from 1981 until her election to House of Commons in 1997.
She was Vice-Chair of Lancashire Enterprises, and served as Chair of the Transport Select Committee from 2008 to 2017.
She is also Chair of Labour Friends of Israel and is Honorary President of the Jewish Labour Movement.
She was appointed a Dame Commander of the Order of the British Empire (DBE) in the 2018 Queen's Birthday Honours List, and is a Vice President of the Jewish Leadership Council.
Ellman resigned from the Labour Party in October 2019, expressing concern over antisemitism in the Labour Party and a potential Jeremy Corbyn-led government.