One of the worst examples of “instant justice” involves a boy aged 15 who was cautioned for rape. His solicitor, Richard Haigh, said: “I was dealing with this boy on another matter — he is now 17 — and this caution was on his record.

“The rape, two years before, involved oral penetration of a younger boy. When the clerk told me about this case I was extremely concerned. An offence like this that involves a younger boy makes it even more of a concern. Understandably, the lad hadn’t wanted this to end up in the Crown Court, so he was happy to take the caution. But it really concerns me that none of this is open to public scrutiny. No one sees what goes on in the police cells.”

The case is one of several involving serious offences that Mr Haigh, of the firm Atteys, in South Yorkshire, has found resulted in a caution rather than a court appearance.

Another client, a man in his mid-twenties, had at least six convictions for assaults on police officers over the past five years. His girlfriend then complained that he had assaulted her and he was cautioned for actual bodily harm. Mr Haigh said: “Domestic violence is sensitive, but a caution for ABH seems wrong.”

A third case involved a man aged 61 who had a criminal record but had been out of trouble for ten years. He was found in possession of £600 of heroin and was suspected of dealing.

“He was charged with simple possession, but when I looked at his record, between his arrest and when he appeared in court for possession, he’d been cautioned for a separate incident of supplying a Class A drug.” Another case of domestic violence involved a man in his late twenties with four cautions for actual bodily harm on the same woman over five months. He was charged with common assault after a fifth attack.

As a defence solicitor, Mr Haigh said he was bound to advise his clients that, if the police made “ludicrous offers”, then it was a “good deal”.

“But as a taxpayer and a member of the community that wants to see criminal justice work, I want consistency and the bad guys locked up. What concerns me is that, instead, the system is being manipulated for purely political and budgetary reasons and public confidence in the system is ebbing away at a great rate.”

Other cases spotted by magistrates as they look at the records of offenders appearing before them include:

• An assault by two women on a pub doorman in Dorset who had refused entry to a 16-year-old with no proof of identity. One woman hit the man over the head and punched him in the face. As he restrained her, the second scratched his face. The women were given conditional cautions and had to pay £100 compensation.

• An attack by a group of youths on Tyneside on a man walking home from a pub. There were verbal exchanges and the victim’s nose was broken by a punch. The youth who hit him had no previous convictions and received a conditional caution, had to pay £100 in compensation and write a letter of apology.

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