Ian Hamilton Shearer, Lord Avonside, PC (6 November 1914 – 22 February 1996) was a Scottish lawyer and judge.

He was standing counsel to Customs and Excise, the Board of Trade and the Ministry of Labour 1947–49, and to the Inland Revenue 1949–51.

[1] He was Sheriff of Renfrew and Argyll 1960–62,[2] and Lord Advocate from October 1962[3] to 1964.

On leaving office, he was appointed a Senator of the College of Justice in 1964,[4] Taking the judicial title Lord Avonside, he filled the vacancy caused by the resignation of Lord Mackintosh, and held the office until 1984.

He was also a Member of the Lands Valuation Court from 1964 (Chairman from 1975 to 1984), Chairman of the National Health Service Tribunal, Scotland 1954–62, a Member of the Scottish Committee of the Council on Tribunals 1958–62, Chairman of the Scottish Valuation Advisory Council 1965–68, and a Member of the Scottish Universities Committee of the Privy Council from 1971.