SUSSEX, N.B. — Answers over the cause of a tragic bus accident that killed four U.S. children travelling through New Brunswick may soon be forthcoming if the chief coroner has her way.

Dianne Kelly, the province’s chief coroner, expects an inquest will be called soon despite a legal deadlock over criminal charges stemming from the crash near Sussex last April.

“We’ll make every effort to make a decision as quickly as we can,” she says. “We don’t want these things delayed unnecessarily.”

Kelly adds her department is already reviewing files on the accident, which raised fears the case could be locked forever in a legal Catch-22. Hin Chi Kan, the 61-year-old driver of the bus, has been charged with careless driving under New Brunswick’s Motor Vehicle Act and a warrant issued for his arrest.

But because the charge is relatively minor, the driver can’t be extradited to Canada and all evidence relating to the accident is locked in a legal limbo.

Neil Sugarman, a member of a group of Boston lawyers representing the families of the dead children, says parents are upset over what they see as a failure of justice in New Brunswick.

“They all understand that he will never show up for a New Brunswick court appearance,” he says. “They are dismayed at the low level of apparent prosecution.”

Sugarman explains the lack of public accessibility to evidence could complicate civil actions under way south of the border. The evidence includes a police report on what happened the morning a tour bus carrying Boston-area schoolchildren to a music festival in Halifax flipped off a sharp turn at the Sussex intersection and slid into a grassy field.

Two boys and two girls sitting in the rear of the bus, ages 12 and 13, died at the scene. Witnesses said the bus driver was going too fast when he approached an intersection and made a wrong turn onto a tightly curling ramp leading to the Trans-Canada Highway. There have also been questions about the safety of the intersection.