A driving instructor who was punched and robbed as she was giving a lesson was left furious and disappointed after a judge told her she was “too believable” to testify against her alleged attacker.

Instead, the judge awarded Denise Dawson £250 from public funds and acquitted the man accused of the robbery.

Judge James Tabor, QC, told the 35-year-old mother of two that she was “honest, utterly decent and brave” but her “impressive” performance in the witness box could sway the jury unfairly.

The case against Liam Perks collapsed because the judge felt that Mrs Dawson’s “three-second” glimpse of the robber was insufficient to ensure a safe conviction.

Perks, 20, who pleaded guilty to an unrelated charge of burglary, had denied robbing Mrs Dawson.

Judge Tabor told Bristol Crown Court: “Denise Dawson was a particularly impressive witness because she showed courage, clarity of thought and was undoubtedly honest. The jury may lend more weight to her evidence than her facts allow. You cannot be sure she got it right . . . had this been the Archbishop of Canterbury’s son, would I have allowed [the trial] to go on? The answer is no.”

The court was told that Mrs Dawson’s pupil Jodie Dickinson, 26, was practising hill starts on the Southmead estate in Bristol in December 2007 when she stalled the car. The back window was smashed by a youth who reached in and grabbed Mrs Dawson’s laptop computer.

Mrs Dawson chased after the youth as he ran off. When she returned to the car another man, whom she identified as Perks, was leaning through the passenger window rifling through the glove compartment. She tried to drag him away but was punched twice in the face by another member of the gang. Mrs Dawson later picked out Perks at a video identity parade.

Mrs Dawson said yesterday that she felt cheated by the judicial system but had no complaint against Judge Tabor. She said: “He was fantastic, but I’m not happy with the system.

“They told me there was insufficient evidence but, if I saw him and can positively ID him, surely that in itself is enough evidence?”

The Crown Prosecution Service defended the decision to prosecute Perks. A spokesman said: “We reviewed the evidence and, in accordance with the Code for Crown Prosecutors, decided that there was sufficient evidence to merit a prosecution.

“After hearing the evidence, the judge made the decision to direct an acquittal. We accept the judge’s decision and have no plans to appeal against it.”

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