Jakarta - THE three convicted Bali bombers filed a petition against firing squads in Indonesia's constitutional court today in a last-ditch bid to stave off their executions, lawyers said. The members of the Islamist Jemaah Islamiyah network - Amrozi, Imam Samudra and Ali Ghufron - are awaiting execution over the 2002 bombings on the resort island that killed more than 200 people, including 88 Australians.