Simpson was arrested last weekend, causing him to miss Snow Patrol’s headline show at Oxegen.
He is alleged to have been found in possession of cocaine in June of last year, and was due to appear at a hearing on the charge. After he failed to turn up at this hearing a warrant was issued for his arrest.
Simpson was taken into custody as he was about to catch a plane to go play Oxegen following the band’s Live Earth gig.
Although this arrest meant he missed his Irish gig, Simpson did get to play the band’s date at T in the Park the next day.
He will appear in court on drugs charges on July 31st. If convicted, it would lead to difficulties getting visas to playing countries like Australia and the US.