A high school coach found guilty five years ago of inappropriately touching a teenage girl should get a new trial. That’s according to the Hawaii Supreme Court.

Keith Matsumoto already served his six-month sentence. So it’s not clear if there will be a new trial.

Matsumoto was convicted by a jury in 2014 of third degree sex assault and was sentenced to six months in jail and five years probation. The long time wrestling coach was accused of groping a 14-year-old female wrestler at a tournament at Farrington High School in 2012.

The Hawaii Supreme Court struck down that verdict Tuesday because while Matsumoto was being questioned by HPD, the detective told him that he did not pass the polygraph test when the results were actually inconclusive. So he then confessed.

The high court ruled “Matsumoto was unable to exercise his right to put forth before the jury … all evidence including the facts and circumstances surrounding the making of his confession.”

“The court said that wasn’t fair, or the jury had a right to hear about all of this that happened and the jury got to hear about none of this,” said David Hayakawa, Matsumoto’s attorney.

According to Court documents the jury never heard about the polygraph test so the supreme court ruled, “The jury was unable to make an informed determination regarding the credibility, reliability, and the weight to be given to Matsumoto’s inculpatory statements,” or confession. As to why Matsumoto would confess if he’d done nothing wrong, Hayakawa says Matsumoto had been questioned for two days straight and just could not take anymore so he gave in.

“The steps that occurred here were likely to produce a false statement and that’s why that was not allowed. Mr. Matsumoto testified I thought if I gave him something and apologized and never coached again it could go away and that’s what happened here,” said Hayakawa.

We asked prosecutors if they will retry the case. A spokesman says they are exploring their options. We asked HPD if the detective will be reprimanded for not telling the truth about the polygraph test. a spokeswoman says no, detectives may use different tools in the course of an investigation.