Robin Thicke Takes the Stand in 'Blurred Lines' Trial

— -- Robin Thicke took the stand Wednesday to face the family of Marvin Gaye, which has claimed his hit "Blurred Lines" ripped off Gaye's song, "Got to Give It Up."

Thicke admitted that "Got to Give It Up" is one of his favorite songs, and that it's a classic.

He'd previously said as much in a TV interview, but then claimed that he gave that quote while under the influence of alcohol and Vicodin.

In a lawsuit they filed in 2013, Thicke, Pharrell Williams and Clifford Harris Jr. (aka, T.I.) defended themselves against reported accusations by Gaye's loved ones that the singers stole parts of "Got to Give It Up," for "Blurred Lines." However, in October, a judge sided with the Gaye family, ruling that their musicological experts had given enough evidence to allow the case to go to trial.

Earlier today, Janis Gaye, the late singer's second wife and mother of his children, Nona and Frankie, was the first witness to take the stand. She said she helps her children regarding the copyrights to their father's song, and that when they have a question they turn to her.

She said that, at first, she thought "Blurred Lines" was great and brought new life to "Got to Give It Up," but later she realized the song's creators had not licensed the rights to Gaye's song.

Throughout the trial, which began Tuesday and is expected to last for two weeks, a jury of five women and three men will listen to the composition and melody of "Got to Give It Up" to determine if there was a copyright infringement.

Some experts believe that this case could have a resounding effect throughout the music industry.

"Artists have drawn upon the inspiration for their songs, listening to other songs," legal expert Alison Triessl told "Good Morning America." "They may not be able to do that anymore."

Lawyers for both parties would not comment.

With reporting by Vania M. Stuelp and Brandi Hitt