She said her son was unaware that the Hollywood star was a "sexual predator".
Shortly after the alleged event occurred last summer, Unruh said she informally spoke with the Nantucket sheriff and only officially reported the matter last week. One man, who remained anonymous, even claimed Spacey tried to rape him as a teen.
The press conference was announced in a press release from the office of lawyer Mitchell Garabedian, who has represented sexual abuse victims of Catholic priests.
Spacey also came out as gay in the same statement saying, "As those closest to me know, in my life I have had relationships with both men and women".
Unruh said an unidentified woman witnessed the incident and "told him to run" when Spacey went to the bathroom of the Nantucket establishment.
News had come that afternoon that Netflix was cutting ties with the House of Cards star after multiple men had accused him of sexual harassment, beginning with actor Anthony Rapp, who told BuzzFeed that Spacey made a sexual advance towards him in 1986, when he was 14. He also publicly came out as gay, which was met with criticism from prominent LGBTQ celebrities. "I want to see Kevin Spacey have the hand of justice come down on him". "That was an appalling attempt to deflect attention away from what you really are: a sexual predator".
Since Rapp made his allegations, Spacey has been hit by at least 10 other claims. A publicist said last week that Spacey is "taking the time necessary to seek evaluation and treatment". "No other information will be available at this time". Netflix says the now filming sixth season will be the last.
A former production assistant who worked on the show in its early seasons detailed an incident where he picked up Spacey and drove for him. Spacey apologized in an October 29 tweet - his last - but also said he had no memory of the alleged encounter.
Assistant Cape and Islands District Attorney Tara L. Miltimore confirmed to the Herald that Spacey, 58, is under criminal investigation. With Spacey being one of the producers of the show and its lead star, this gave him power on the set and prevented the crew member from coming forward and telling his story.