The 24-year-old Derry man was shot dead by vigilante group Republican Action Against Drugs (RAAD) in Buncran on February 9, 2012.
Donegal Coroner Dr Denis McCauley, sitting in Buncrana Court House on Thursda, said Mr Allen’s Inquest would take place on Wednesday, September 11, 2019.
Mr Allen, who was from the Waterside area, had been living in Links View Park, just outside Buncrana at the time of his brutal murder.
RAAD – a vigilante style group made of former members of the Provisional IRA and INLA – later claimed responsibility for his killing.
The group claimed he was involved in drug-dealing.
Mr Allen’s family has totally refuted RAAD’s claim.
Dr McCauley said Mr Allen’s case was moving into its seventh year and he felt it was important an inquest was held.
Garda Inspector Eugene McGovern agreed with the Cororner.
He said he had had a meeting with the senior detective investigating Mr Allen’s murder.
The detective told Inspector McGovern investigation was continuing and there were matters outstanding.
Inspector McGovern said an inquest into the murder should now take place.
A number of suspects were arrested last year in Donegal over the murder but were later released without charge.