The co-defendant in the the Tulisa Contostavlos trial has also walked free after the judge decided the case against him could not proceed.
Rapper Michael Coombs, whose stage name is Mike GLC, had pleaded guilty before the trial to supplying half a gram of cocaine to undercover reporter Mazher Mahmood.
On hearing the decision the 36-year-old reportedly wept and hugged his defence barrister, Jeremy Dein QC.
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Downpours keeping us on our toes today
The M20 in Kent has been closed in both directions after a pedestrian bridge allegedly collapsed on the motorway on Saturday.
The AA have warned of traffic jams and urged people to carry extra water in their vehicles because of the warm weather.