Trevor was just 22 years old when he disappeared after his work Christmas night out in December 2000.
His last movements were caught on CCTV as he walked towards home. Despite searches and his family mounting a huge campaign to find him, Trevor was never found.
But now, 17 years later, a review of his case has found a number of leads which detectives are taking very seriously.
The Irish Independent reports that detectives received information from an informant in recent months, who has alleged that a well-known Crumlin criminal is responsible for Trevor's murder. It is believed the informant told investigators that the alleged suspect shot Mr Deely and concealed his body.
It has prompted them to seal off a three-acre wooded site in the Chapelizod area of Dublin to facilitate an extensive Garda search.
Det Insp Paul Costello told reporters this weekend that Gardaí would be keeping an "open mind" as the examinations developed.
Mr Deely was last seen on the morning of December 8, 2000, in the Haddington Road area of the city centre. Newly-enhanced footage was released by Gardaí in April showing Mr Deely talking to a man dressed in black outside the Bank of Ireland on Baggot Street. They believe the man proceeds to follow the 22-year-old along Haddington Road as he makes his way home.
Despite appeals to the public - this man in black has never come forward.
Mr Deely's missing case has never been closed. His family now hope that this dedicated unit reviewing his disappearance can give them the closure they so desperately need.
