Burgas Regional Court has put Nikola Burgazliev, who is on trial over the quad bike crash in Sunny Beach, under house arrest with an electronic tag.
The ruling is not final. It can be appealed to the Court of Appeal within seven days. One of the judges gave a dissenting opinion.
Burgazliev, from Nessebar, is on trial over the death of a woman and the serious injuries to her son and two other people in the crash at the resort. He spent more than 14 months in custody.
The court ruled on an appeal by Burgazliev and his lawyers. He cannot leave home without permission, and he needs the court's approval to travel outside Bulgaria.
The judges said the evidence still supports a reasonable suspicion that he was involved in the crime, but there are no longer enough specific grounds to keep him in custody. They took into account his clean criminal record, his family ties in Bulgaria and the lack of any violations during his earlier house arrest.
The court said the risk that he could go into hiding has not fully gone away, but electronic monitoring gives the control needed. The judges said custody cannot serve as advance punishment for the severe consequences of the crash. Whether Burgazliev is guilty, and what sentence he should get, will be decided when the hearing of evidence ends. It is still under way.
Burgazliev claims the "brakes failed". But at an earlier hearing, vehicle experts found that the braking system was never used at all. Another hearing showed gross failings in the police's first checks after the crash.