Sir Thaddeus Pearcey McCarthy ONZ KBE (24 August 1907 – 11 April 2001) was a New Zealand jurist. McCarthy was educated at St Bede's College, Christchurch, and then studied law at Victoria University College, New Zealand and graduated in 1928. He was admitted as a solicitor only in 1929, completed an LLM degree (in 1930), and in 1931 was admitted as a barrister. He practised at the Wellington bar for 26 years until his appointment to the bench. McCarthy was in active service overseas during the Second World War. He prosecuted Walter James Bolton, who was executed in 1957, the last person executed in New Zealand.