The number of errors by the Criminal Records Bureau (CRB) has more than doubled in the past 12 months, despite intense pressure for it to improve its performance.
Many of the victims of mistakes would have been intending to take up jobs as teachers, nurses and childminders, or become youth volunteers.
Hundreds of innocent people have been accused of wrongdoing by the CRB.
They are likely to have faced career problems or stigma from their communities as a result.
They will also have had to go through an appeals process to clear their names.
The disclosure is likely to deter innocent people from applying for positions that require scrutiny, for fear of being labelled a criminal.
The worsening figures are an embarrassment for the Home Office, which faced criticism after the number of errors by the bureau was first highlighted last year.
The latest figures show that 1,570 people being checked by the CRB were wrongly given criminal records, mistakenly given a clean record or accused of more serious offences than they had actually committed in the year to March 31.
This compares with 680 people in the previous 12 months.
The Home Office also pointed out that 90 per cent of disputes were resolved within 21 days.