He became MP for Cleveland and Whitby in 1974, and became an opposition spokesman in 1976. He was made a Queen's Counsel in 1978. Between 1979 and 1981 he was Minister of State at the Home Office, and then was made Chief Secretary to the Treasury, a cabinet position. At the 1983 election his seat changed to Richmond. He was Secretary of State for the Home Department from 1983 to 1985, and was then moved to Secretary of State for Trade and Industry. He resigned over the Westland affair.
He was made a commissioner at the European Commission in 1989, resigning as MP at this time, and became vice-president, but resigned with the rest of the comission in 1999 amid accusations of widespread fraud.
He was created Lord Brittan of Spennithorne in 1999 and is an advisory director to Unilever.