Tulisa Contostavlos is "absolutely convinced" that she was not over the limit when she crashed her Ferrari on Thursday (10.09.15).
The former 'X Factor' judge slammed into another car after travelling on the wrong side of the road near her home in North London around midnight and was arrested by police after failing a breath test.
However, Tulisa says she only had one drink, a vodka, before leaving her house and does not believe she had drank too much to drive.
A source told the Sunday Mirror newspaper: "Tulisa had just one drink, a vodka, and it was only a few minutes earlier - but she needed to pop to the shops for a few bits. She was careful not to have another drink and jumped in the car.
"By the time she was breathalysed it was around 20 minutes later and she was confident that she would pass the test. But the machine flickered right on the bring before coming back positive."
Tulisa, 27, later gave a second sample and is now waiting for the results.
The insider added: "She is completely convinced she hadn't drunk too much to drive. Now she has to wait to find out the results of that sample."
Tulisa was released on bail after 22 hours in custody and is due in court in November.
A spokesperson for the Metropolitan Police said: "Police were called following reports of two cars in collision shortly after midnight. There were no reported injuries.
"One of the drivers, a 27-year-old woman, was arrested on suspicion of drink-driving."
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