He represented the Tauranga electorate in Parliament from 1972 to 1984, when he died, shortly before the 1984 election. Previously there had been a controversy over claims by Allen that he had been attacked while walking through the city at night. It was reported he had diabetes, and some concluded he may have been hallucinating or was intoxicated. A detailed account of the Keith Allen affair is provided by Sir Robert Muldoon in his book "Number 8" on page 154. In it he discusses the intrigues surrounding Allen's claim that he had been assaulted, the media fracas and a leaked medical report. What Muldoon doesn't state is that Allen was finding the job of a cabinet minister stressful and wanted to resign. Muldoon would not accept his resignation, according to Barry Gustafson in his biography on Muldoon entitled "His Way". In the documentary "Muldoon: The Grim Face of Power" reference is made to these events. It is claimed that National's Senior Whip met Muldoon on Keith Allen's behalf to explain that Allen wanted out of the Cabinet and wished to retire at the next election. Muldoon retorted: "You look after the back benchers and I'll look after the Ministers.You keep away from Keith Allen". Keith Allen was replaced by Winston Peters.