BOSTON — A young man who accused Kevin Spacey of groping him at a resort island bar in 2016 has filed a lawsuit against the actor, who is also fighting a criminal charge stemming from the alleged assault.

The lawsuit, filed Wednesday, seeks unspecified damages for “severe and permanent mental distress and emotional injuries.”

The accusation was first brought in 2017 by the former Boston TV anchor Heather Unruh, who said Mr. Spacey got her then 18-year-old son drunk and sexually assaulted him at the Club Car, a restaurant and bar on Nantucket where the teenager worked as a busboy.

[Smartphone in Kevin Spacey sexual assault case is missing.]

Mr. Spacey, who has denied groping the young man, pleaded not guilty to indecent assault and battery in January. His lawyers have accused the man of lying in the hopes of winning money in a civil case against the two-time Oscar-winner.