Recalling the night, Andrea Swift said her daughter expressed bewilderment that she had "thanked" Mueller and his then-girlfriend after the incident.
In her testimony, the pop star was cordial, but direct and sometimes testy while being questioned by a lawyer representing Mueller.
The photographer who took pictures at the meet and greet also testified in court spoke in favour of Taylor Swift telling the court that she thought Swift had made a amusing move during the photo, at first believing she had tripped.
"He saw your client lift my skirt".
Melchor says Mueller was devastated by the accusation. Two days later, Mueller was sacked from his $150,000 job -- his "dream job", he said - as a radio DJ. They drifted apart late in 2013, but Melchor says they remained friends.
Though Swift never sought legal action against Mueller, her team did immediately take her complaint to KYGO.
Speaking in court, Swift refused to back down or give ground to the DJ's lawyer.
Two years later, Mueller sued Swift for $3 million, claiming her allegations were false, and led to a loss of income because he was let go from his job. He says she sometimes told him he was "too mean" and since it appeared she wanted to finish the meet-and-greet, he stayed put.
Swift is now a party to an action that is taking place in the federal court system in Denver, Colorado.
"I didn't need a picture". "Resolution of this counterclaim will demonstrate that Mueller alone was the perpetrator of the humiliating and wrongful conduct targeted against Ms".
He described a long and close personal and professional relationship with Mueller.
In the image, shown to jurors during opening statements but not publicly released, Mueller's hand is behind Swift, just below her waist. She countersued, accusing him of assault and battery.
After witnessing some of the most withering testimony ever given, today the jury heard from Swift's former bodyguard, Greg Dent. Swift testified the photo captured the exact moment she was groped.
A member of Swift's security team later confronted Mueller, and a representative for the singer ultimately lodged a complaint with the radio station.
Creative types who work across from the courthouse where Taylor Swift's groping trial is playing out are showing their support for the songstress - using the power of the Post-it.
"He grabbed my ass underneath my skirt", the pop star testified.
Swift Thursday saw Taylor Swift on the stand in Colorado, testifying about the night in 2013 that she claims deejay David Mueller groped her during a backstage meet-and-greet.
Andrea Swift said she did not contact police in order to protect her daughter, saying she did not want the incident to "define her life". "But in the larger discussion about sexual assault, as we've seen, justice can be selective".
When the possibility was suggested that Mueller may not have been the person who groped her.
Taylor alleged that Mueller groped her butt during a meet-and-greet back in June 2013 and the DJ was sacked from his job two days later.
Her defiant, hour-long testimony came four days into a rapidly moving trial that is scheduled to last almost two weeks.