The Legal Aid Agency (LAA) has spent more than £93m funding defence counsel in cases that did not go to trial, the National Audit Office has found.

According to the public spending watchdog’s Efficiency in the criminal justice system report, published today, two-thirds of cases did not progress as planned despite case management improving since 2010-11.

The proportion of trials that go ahead as planned in the magistrates’ court increased from 34% in the year ending September 2011 to 39% in the year ending September 2015. The proportion of Crown court cases that collapsed on the day of the trial fell from 30% to 24%.

However, in 2014-15 the LAA funded defence counsel ‘to the tune of £93.3m’ to represent defendants whose cases never went to trial, excluding guilty pleas. The Crown Prosecution Service spent £21.5m preparing cases that were not heard in court.

The report states that police officers in London who spend a day waiting to give evidence cost £139 a day. Expert witnesses, whose legal aid hourly rates vary between £40-£200, may still be paid even if a case does not progress as planned.

Although fewer cases were entering the criminal justice system, the NAO backs up the lord chief justice's assertion that cases have become more complex.

The number of sexual offences cases in the Crown court has risen by 12% in the past five years, from 9,178 in 2010-11 to 10,309 in 2014-15. The CPS 'expects a further rise’ in 2015-16. This includes ‘historic’ sex abuse and child sex abuse cases, involving vulnerable victims and witnesses.

In magistrates’ courts, the number of domestic violence cases, which require ‘significant victim support’, has increased.

Prosecutions for other serious offences are also increasing, including terrorism, organised crime, drugs and fraud. 'These cases can involve complex evidence, and trials with multiple defendants,' the report states.

In the Crown court, backlogs increased by 34% between March 2013 and September 2015. The waiting time for a hearing has increased from 99 days to 134 days since September 2013.

The report also highlights ‘significant regional variation’ in performance.

A victim of crime in North Wales has a seven in 10 chance that the trial will go ahead at Crown court on the day it is scheduled. This drops to a two in 10 chance in Greater Manchester.

In 2014-15, the length of time between the offence and completion of the case ranged from 243 days in Durham to 418 days in Sussex.

Citing examples of inefficiencies when a case comes to court, the report states that court listing was the ‘single most common reason’ that a case had to be rescheduled last year, accounting for 21% of ineffective trials in the Crown court and 30% in the magistrates’ court.

In some cases, technology and facilities ’may not function as intended’. During one of its case study visits, the NAO witnessed a trial where ‘the police had so little faith in the court’s equipment that they told us they hired their own at a cost of £500 a day’.

Concluding that the criminal justice system is ‘not currently delivering value for money’, the report recommends that the Criminal Justice Board agree on what ‘good’ looks like for the system as a whole.

With 'no common view of what success looks like', the NAO says organisations 'may not act in the best interests of the whole system'.