Cape Town - Katy Perry has lost a copyright lawsuit for her 2013 hit Dark Horse.
A jury has ruled she had copied the Christian rap song Joyful Noise.
Katy and her collaborators, including Juicy J and producer Dr Luke, were accused of copying the melody from Marcus 'Flame' Gray and Chike-Ojukwu.
During the case, Katy and her attorneys reportedly experienced a few technical difficulties when they tried to play Dark Horse over the courtroom sound system.
To help overcome the difficulties, Katy offered to help, saying: "I could perform it for you live".