Taylor Swift appeared in court in Denver, Colorado on Monday during the first day of jury selection for her case against radio DJ David Mueller, in which she is accusing him of assaulting her when a photo was being taken.

The radio host and his then girlfriend attended a meet-and-greet with Swift before her concert in Denver on June 2, 2013, where she alleges he put his hand under her dress and groped her while the photographer took the picture.

In her deposition for the trial, the 27-year-old pop star said: "It was not an accident, it was completely intentional, and I have never been so sure of anything in my life."

Mueller, who denies the allegation, was fired from his $150,000 a year job as a morning host at radio station KYGO two days after the alleged incident. In 2015, he filed a lawsuit claiming that Swift's allegations had cost him his job and damaged his professional reputation. He is seeking $3 million in damages.

A month later, Swift countersued Mueller, accusing him of assault and battery. She is seeking a nominal $1 in damages but hopes the case will "serve as an example to other women who may resist publicly reliving similar outrageous and humiliating acts."

On Monday, she appeared in the courtroom for jury selection as Judge William J. Martinez and lawyers from both sides questioned potential jurors for four hours.

No jurors have yet been selected, according to The New York Times.

Both Swift and Mueller are expected to testify during the court case.

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