Britain's first youth crime commissioner said she was "truly sorry for any offence" caused.
Paris Brown, 17, from Sheerness, Kent, was appointed to the £15,000-a-year post only last week.
Speaking at a press conference in Maidstone, Kent, Miss Brown said she had "taken the decision to decline the offer of the position" as she felt recent media attention would affect her ability to carry out the job.
She added: "I am truly sorry for any offence I have caused."
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