[2] His brother Fergus (Patrick) Barrett OFM, became a Franciscan priest, and founding rector of St John Vianney Seminary, Pretoria, South Africa.

[3] He was elected to Dáil Éireann on 14 March 1968 at the by-election in the Clare constituency,[4] held following the death of Fine Gael TD William Murphy.

After Fianna Fáil's landslide victory at the 1977 general election he was appointed to the cabinet as Minister for the Environment.

After the February 1982 general election Fianna Fáil were returned to office, but Barrett was not appointed to cabinet.

He remained there until 1984, when he won a seat in the Munster constituency at the European Parliament election and was replaced on the front bench by Noel Treacy.