NANTUCKET (CBS/AP) — Prosecutors dropped the groping case against Kevin Spacey on Wednesday. The actor was facing a felony charge of indecent assault and battery on Nantucket.

Cape & Islands District Attorney Michael O’Keefe said in a court filing that he was filing a Nolle Prosequi “due to the unavailability of the complaining witness.”

Spacey was accused of groping a then 18-year-old at the island’s Club Car bar three years ago. The accuser said Spacey allegedly bought him several alcoholic drinks, then groped him.

But the prosecution’s case appeared to fall apart at a hearing surrounding the accuser’s missing cellphone. The alleged victim asserted his Fifth Amendment right against self-incrimination and refused to testify further after being questioned about text messages the defense claims were deleted.

The cellphone has been a key issue in the case against Spacey. The accuser and his mother, former Boston TV news anchor Heather Unruh, said they gave a cellphone to prosecutors in December of 2017 and that they never got it back. Unruh told investigators that she deleted items concerning her son’s “frat boy activities” from the phone before giving it to authorities.

The man’s decision not to testify caused Judge Thomas Barrett to question the viability of the case against the two-time Oscar winner, whose career collapsed in 2017 amid a string of sexual misconduct allegations.

On Sunday, prosecutors met with the accuser and his family to discuss the case.

“The complaining witness was informed that if he chose to continue to invoke his Fifth Amendment right, the case would not be able to go forward,” O’Keefe said in a statement.

The accuser said he would not waive his Fifth Amendment right, and prosecutors told him the only way to continue the case would be to “indict the defendant, immunize the complaining witness and force his testimony.” That process would make “further prosecution untenable,” O’Keefe said.

The accuser’s lawyer, Mitchell Garabedian, released a statement Wednesday afternoon.

“My client and his family have shown an enormous amount of courage under difficult circumstances,” he said. “I have no further comment at this time.”

The development in the criminal case comes about two weeks after the accuser dropped the lawsuit he filed against Spacey. Garabedian said the lawsuit was dropped because the accuser is on an “emotional rollercoaster.”

The accuser was working as a busboy at the Club Car at the time of the alleged assault. He told police he went over to talk to Spacey after his shift because he wanted to get a picture with the former “House of Cards” star. He said Spacey bought him several drinks and tried to persuade him to come home with him before unzipping the man’s pants and groping him for about three minutes.

Unruh’s son told police he tried to move Spacey’s hands, but the groping continued, and he didn’t know what to do because he didn’t want to get in trouble for drinking because he was underage. The man said he fled when Spacey went to the bathroom.

WBZ legal analyst Jennifer Roman wasn’t surprised by the DA’s filing. She says without the alleged victim testifying and the missing cellphone, there is no evidence to prosecute.

“Really what the prosecution would have really relied on if they didn’t have their victim was the cellphone because it would have fallen under what’s called an ‘excited utterance’ which is a hearsay exception and would allow that cellphone and the text messages on that cellphone to speak for the victim even if the victim himself wasn’t testifying,” Roman said. “So once you knock out the alleged victim and you knock out the cellphone there is nothing.”

Shortly after Spacey was charged, he posted a video on YouTube in the voice of his “House of Cards” character who was killed off after the sexual misconduct allegations emerged, saying “I’m certainly not going to pay the price for the thing I didn’t do.”

Spacey has faced several other accusations.

His first accuser, actor Anthony Rapp, said Spacey climbed on top of him on a bed when Rapp was 14 and Spacey 26. Spacey said he did not remember such an encounter but apologized if the allegations were true.

(© Copyright 2019 CBS Broadcasting Inc. All Rights Reserved. The Associated Press contributed to this report.)