While on the witness stand in a Los Angeles courtroom, the performer sang and played a short piano medley of U2's "With Or Without You," The Beatles' "Let It Be," Alphaville's "Forever Young," Bob Marley's "No Woman No Cry" and Michael Jackson's "Man in the Mirror," according to The Hollywood Reporter.
The reason for the performance? It's part of his legal team's efforts to try and prove Thick, Pharrell Williams and T.I.'s hit song doesn't infringe on Marvin Gaye's "Got To Give It Up."
Gaye's family sued the songwriters over the tune in 2013.
In court Wednesday, THR reports, Thicke's attorney had the singer compare phrases from the songs and compare their chord structures, in an effort to demonstrate that many songs have similar chords and melodies without copying one another.
His testimony also addressed statements he made in a deposition last year saying he was drunk and high on Vicodin while recording "Blurred Lines" and in interviews following its release.
Thicke said the reason he took credit despite his minimal role in writing the track was because he was jealous of Williams' work. "I felt it was a little white lie that didn't hurt his career but boosted mine," he said.
The trial is expected to run for eight days and include testimony from Williams, T.I. and Thicke's ex-wife, Paula Patton, who co-wrote "Love After War" (which Gaye's family claims copies his "After the Dance").