Police and CPS staffing levels may have been a factor in shortcomings surrounding the disclosure of evidence, the Lord Chief Justice has suggested.

Lord Burnett of Maldon, the head of the judiciary in England and Wales, said problems were “inevitable” given the agencies responsible for the work have fewer people.

Confidence in the criminal justice system was rocked last year after a flurry of cases collapsed following serious failings.

In the lead-up to trials, officers and prosecutors are required to hand over relevant material that either undermines the prosecution case or assists the defence case.

But the regime came under sharp focus after defendants facing rape allegations had the charges against them dropped when critical material emerged at the last minute.

The revelations prompted a review of every live rape and serious sexual assault case in England and Wales.

Appearing at the House of Lords Constitution Committee, Lord Burnett described the issue as a matter of “great concern”.

He said: “At the heart of disclosure problems in the criminal context seem to me to be very straightforward propositions that the people who are responsible for ensuring disclosure occurs in accordance with the statutory scheme are under an enormous amount of pressure.

“What we’ve been seeing in a number of the cases that have gathered a lot of public attention is that disclosure happens right at the end and often only under pressure from assiduous prosecutors or defence solicitors and advocates.

“I just wonder whether that is a phenomenon which reflects the fact that those who have to do this work have got too much to do because there are fewer of them and they put things off.

“When you’ve got fewer people both in the police and the CPS, fewer people doing the same amount of work, inevitably there will be problems.”

Police and the CPS have pointed to an “explosion” in the volume of digital material created in criminal investigations.

Lord Burnett said: “The enthusiasm with which people text each other is such that people have thousands and thousands and thousands on their phones.

“The sensible use of technology itself must surely be able to help.

“But I know what will be said: get new technology to search phones or to search a complainant’s emails, that will require somebody to invest quite a lot of money in providing the equipment to do it. So I can well envisage the sort of political debate that will be going on.”

Following his remarks, the National Police Chiefs’ Council said that getting disclosure right is a “fundamental part” of a fair criminal justice system and there was now an “unprecedented focus” on finding long-term solutions to the failings.

An NPCC spokesman added: “We do have a shortage of detectives and they have many complex demands on their time so measures to ensure they better understand disclosure, have clear processes and the right support from experts are at the centre of our action plan. 

“In the longer term, we are looking at how technology can help us to meet the huge challenge of ever increasing volumes of data involved in each case.”

Elsewhere, Lord Burnett highlighted the problem of abuse that is hurled at judges on social media and the internet.

He said: “There’s no doubt that it’s dispiriting and it’s sometimes genuinely frightening for some of our judges.

“It’s not right that any public servant should be put in fear for themselves or their families.”

He raised concerns that the abuse could put off prospective candidates from joining the judiciary.

The Lord Chief Justice highlighted the wider issue of difficulties in recruitment and retention of judges, saying they “pose a threat to our ability to discharge the business of the courts effectively”.

On Wednesday the Government announced a new online learning platform amid efforts to give people from all legal backgrounds greater support to apply to become a judge.