Pop star George Michael has pleaded guilty to driving while unfit through drugs.The 43-year-old singer made the plea after he was ordered by District Judge Katherine Marshall to attend the first day of the trial at Brent Magistrates' Court in north-west London.The Crown Prosecution Service dropped an alternative charge of being in charge of a vehicle while unfit through drugs on October 1 last year.The singer, who wore jeans, a black shirt and a black jacket, originally sat in the wrong seat in the courtroom and the judge ordered him to take his place in the dock.And Michael, whose birth name is George Panayiotou, appeared confused when entering his plea, claiming he was guilty due to "tiredness and prescribed drugs"He told the court he was "very ashamed" of his drug-driving charge and that he had done something "very stupid".Taking the unusual step of speaking directly to Judge Marshall, he said: "I have only been aware for the last 15 minutes that this was a possibility to address you in an open court. I just want to be as brief as possible."There are two reasons we are here today. I did something very stupid and I am very ashamed since doing it. I'm not used to defending myself in a position where I am ashamed of something."If I had known the day after the charge was brought the legal option of accepting a punishment without taking responsibility for something I felt I was not guilty to I could have saved everyone here a lot of time and trouble."But I genuinely believe that I only knew the full possibility of this in the last week and as soon as I took on Mr Spiro (his current counsel) I realised that I had been in a combination of misinformation and shame for about eight months."I really have been very distressed by this whole thing. I am perfectly aware that I did something very wrong and got into my car when I was unfit to drive."I was not in my normal physical state and I'm perfectly prepared to accept the correct punishment for that and I would have accepted it a long time ago. It was fairly predictable considering how much work I had done that week."However, the judge did not believe that Michael's previous counsel was to blame.Michael's sentencing was adjourned to May 30 to enable more blood tests to be carried out.© Independent Television News Limited 2007. All rights reserved.