HOLLYWOOD—Even celebrities go to trial. Taylor Swift, 27, is on trial, and is “absolutely certain” she was groped by a Colorado radio DJ, a court has heard. Swift accuses broadcaster David Mueller of slipping his hand under her dress while they posed backstage together at one of her 2013 concerts. Her attorney said in his opening statement at the court in Denver, Colorado, that Mr. Mueller had “grabbed her rear end.”

Mr. Mueller sued the singer in September 2015, calling her allegations false. He said she had cost him his $150,000 a year job, as a host at a country radio station. He was fired on June 4, 2013, two days after the alleged incident. The 55-year-old claims this was due to pressure from Swift’s team, who handed over the photograph to his bosses. Two years after the incident, Mueller sued Swift, claiming her allegations cost him his job and damaged his professional reputation. Swift responded with her own lawsuit. One month after, the star countersued Mueller for assault and battery, saying she felt “frantic” and “distressed” after the incident. In a deposition filed in 2016, Swift described “feeling violated in a way I had never experienced before.

Fans are flocking to see the trial, however, only 32 seats are available, because the trial is open to the public. Ms. Swift — who was in court on Tuesday — countersued a month later, saying what occurred at the city’s Pepsi Center was assault and battery. On August 8, jurors were shown a photograph of the alleged assault and battery. They were also shown a photograph of the alleged assault at a VIP room meet-and-greet before the gig on June 2, 2013. Her fans, known as Swifties, waited outside court from the early hours for a chance to witness the case. Taylor, who was 23 at the time of the incident, is suing Mr. Mueller for the symbolic amount of $1. She was accompanied in court by her mother Andrea.

So what does Mueller want? He’s looking for his name to be cleared, and $3 million in damages. So will Taylor testify? The trial is expected to last nine days, but it unclear when Swift will take the stand. Other witnesses expected to take the stand  include the star’s mother, Andrea, and the photographer employed for the meet-and-greet. As far as the defense, Mueller’s then-girlfriend Shannon Melcher will testify about the taking of the photograph and the DJ’s character. Get this, no jurors were selected on the first day, many were dismissed. One said on her questionnaire that she found Ms. Swift “petty and dishonest.” Another was struck from the pool after saying he had friends who had experienced assault, and was unsure he could be impartial.

Back in July 2012, Kevin Costner sued, taking a bold shot against the independent studio, Morgan Creek Productions of hiding profits from him for the 1991 hit “Robin Hood: Prince of Thieves.” The lawsuit claimed he got no profit participation statements in 2010 and 2011 and late statements from 2004 to 2009. Costner accused Morgan Creek of diverting money by assigning foreign distribution rights on “Robin Hood” from Morgan Creek to a foreign company owned by Morgan Creek CEO James Robinson.

The film grossed about $390 million when it came out in theaters. At the time the lawsuit was filed, Robinson said that Costner had already been paid more than $40 million for his work on the movie. Before going to trial, the case was settled, for an undisclosed amount.

Rose’s Scoop: Actress Jennifer Lawrence was photographed by Annie Leibovitz for Vogue’s September issue. You may recall back in 2014, according to published reports, intimate images of the Oscar-winning actress were published online.