Peter became a member of the DUP at its foundation and has been an Executive member from 1973. He was elected Secretary of the Central Executive Committee in 1974 and appointed as first General Secretary of the party in 1975. He was elected Deputy Leader in 1980, a post he held until he was elected unopposed as Leader on 17th April 2008 following the retirement of Dr Paisley.
Peter served as member of Parliament for East Belfast from 1979 until 2010 where he was the longest serving member of the Northern Ireland Select Committee. He was also the longest serving Member of Parliament for any Belfast constituency since Parliamentary representation began after the Act of Union in 1800. He was appointed a member of the Privy Council in 2007.
He was elected to the Northern Ireland Assembly which existed between 1982 and 1986 where he served as Chairman of the Environment Committee. He was also elected to the Northern Ireland Forum and served in it until it completed its work in 1998.
Peter was elected to the Northern Ireland Assembly in 1998 representing East Belfast and again in 2003, 2007 and 2011. During this time Peter served as both Minister for the Department for Regional Development and Finance Minister. Peter was installed as First Minister of Northern Ireland at a special sitting of the Northern Ireland Assembly on 5 June 2008.
Peter is without doubt one of the longest-serving and most respected politicians in the UK.
In July 2007 Peter stepped down from his position as Alderman on Castlereagh Borough Council bringing to an end 30 years service to the Borough. During this time he had served as Deputy Mayor (1978), Mayor (1986) and as an Alderman since 1988. He had also been DUP Group Leader during his time on the Council and was instrumental in the development of the Dundonald Ice Bowl. In recognition of Peter’s contribution to the Council, in 2003 both political colleagues and opponents voted to bestow upon him the ‘Freedom of the Borough’.