The unarmed Tibble chased Quinn on his motorbike and, while attempting to stop him, was fatally shot twice in the chest.
[3] Quinn escaped to Dublin in the aftermath of the shooting and served a short prison sentence after his arrest for assaulting a police officer there.
After his release in 1978 he returned to his hometown of San Francisco but was arrested in 1981 and later extradited to England in February 1988 where he was convicted of murder and jailed for life with a recommended minimum term of 35 years.
Quinn served 11 years before he was released in April 1999, aged 51, along with the Balcombe Street Gang, under the terms of the Good Friday Agreement.
[4] While with the IRA, Quinn adopted an Irish accent[5] and was tagged with the nickname "Yankee Joe" because of his American origins.