The Biebs might just have admitted to illegal Xanax use in a deposition video posted by Radar Online.

The 'Baby' singer was asked, "Do you have a prescription for Xanax?" to which he replied to with "No, sir." JB's lawyer whispered to the pop sensation after the question, saying something along the line of giving him [the lawyer] a chance to object.

Interestingly, Xanax was reportedly found in the Biebs' system - as shown by his DUI blood work, notes Radar Online. According to the Daily Mail, urine test also revealed marijuana and Xanax in his system. Justin has already admitted that he has smoked marijuana before the arrest, says the Daily Mail, but not Xanax.

"Xanax is used to treat anxiety disorders, panic disorders, and anxiety caused by depression," defines drugs.com. Users of the drug are advised against consuming alcohol while taking the medication as drugs.com notes that the anti-anxiety drug can "increase the effects of alcohol."

Daily Mail notes that Bieber's blood alcohol level was well below the .02 threshold considered intoxicated for underage drivers.

"Xanax is a drug of abuse and you should be aware if anyone is using your medicine improperly or without a prescription," says drugs.com. Individuals who stop using Xanax may reportedly have seizures or exhibit withdrawal symptoms, adds the website.

Justin Bieber's alleged illegal Xanax use is not a first in Hollywood history and certainly not a first in his circle. As previously reported, the pop sensation's ex-GF, Selena Gomez, has also been rumored to have entered a rehab facility for prescription drug abuse.

According to the report, the 'Come and Get It' singer has voluntarily entered a rehab facility in Arizona for two weeks to mend her broken heart and for Xanax and Ambien abuse.

'The Hunger Games' star Philip Seymour Hoffman's medical report from the New York City medical examiner also revealed Xanax among other drugs in his system which allegedly comprised a "toxic mix" leading to his death, says the Miami Herald.

Watch JB's deposition video below regarding alcohol and drug consumption, courtesy of Radar Online.