I started my career as a criminal defence lawyer with the famous words of Viscount Sankey LC firmly in mind: 'Throughout the web of English criminal law one golden thread is always to be seen. No matter what the charge or where the trial, the principle that the prosecution must prove the guilt of the prisoner is part of the common law of England and no attempt to whittle it down can be entertained.'

I had an unshakeable belief that British justice was the best in the world and was proud to be part of the system. The shameful miscarriages of justice that led directly to safeguards such as the taping of interviews and the formation of the Crown Prosecution Service independent of the police were still recent enough that the right of the innocent man not to be wrongly convicted was beyond compromise.

Over the years, it has become a common perception that acquittals are more often than not simply guilty people getting away with it. Victims’ interests have rightly received greater attention, and many of the measures designed to improve conviction rates have been justified: requiring the defence to identify their case before trial, the spectre of adverse inferences when defendants fail to answer police questions or provide an account from the witness box, the reliance in appropriate cases on evidence of previous convictions and, most recently, the introduction of detailed rules of criminal procedure and the greater role of the courts in active case management.

The primary objective of criminal justice should be to convict the guilty and acquit the innocent. In the rush to achieve the former we should not forget the latter. Sadly, imminent changes affecting the recovery of costs by a successful non-legally aided defendant have severely undermined the value we place on the rights of the innocent. For cases commenced after 1 October 2012, the reimbursement of legal costs incurred by an acquitted defendant are restricted to legal aid rates, far lower than lawyers involved in any other type of work (or most tradesman) would expect to be paid: £3.90 for a letter hardly covers the cost of the stamp. Unfair as it is, this reflects the harsh realities at a time of unprecedented economic difficulty and strains on public resources.

My concern, however, relates particularly to those cases dealt with at the Crown Court, where the changes mean it will no longer be possible for the innocent defendant to obtain reimbursement of any privately paid legal costs at all. The justification for this is that in the Crown Court legal aid is available to everyone, although those earning above a certain amount are required to pay contributions, of up to £900 per month, which are refundable on a not guilty verdict.

Let me be clear, I have enormous respect for my colleagues who continue to carry out legal aid work, providing representation for the vast majority of those accused of serious crime who would otherwise be unable to afford it, but the funding constraints make it impossible to provide the level of service of a solicitor working at a reasonable fee on a far smaller caseload. For those who have a choice, not all of them want to instruct a solicitor at legal aid rates. When you instruct a lawyer you are not buying a tin of beans. If you need surgery, you want the best surgeon you can get; you expect him to be suitably paid, and might have concerns if told he was paid less than your plumber. If you are putting an extension on your house, you might not necessarily choose the lowest quote.

It is bad enough that, under the changes, the person wrongly accused of a crime is prevented from recovering all of his fees reasonably incurred in proving his innocence. To impose on those possibly facing the most serious allegations the potential choice of going with a solicitor working at bucket-shop rates or instructing one at a proper fee - but with no prospect of getting any of it back once their innocence is established - is positively shameful.

We have entered an age in which the golden thread, it seems, comes only at a price.

Timothy Ryan is a partner and solicitor at Warners Law

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