A justice campaign group has called for a debate about the future of the magistracy after publishing figures which appear to show increasing numbers of lay magistrates being replaced by district judges. 

The number of magistrates has plummeted by 20% since 2008, while the number of district judges has grown by 4% in the same period, according to research from charity Transform Justice.

Although the number of prosecutions has declined by 14% in four years, it is unclear why magistrate numbers have gone down while district judge numbers have gone up, said the charity.

According to a parliamentary response, district judges cost the taxpayer nearly three times more per hour (£92) than a bench of lay magistrates. The average cost of deploying a district judge in 2012/13 was £171,673, compared with £60,720 for a bench of three magistrates.

The research reflects a growing tension between lay magistrates and the paid judiciary. 

An unnamed magistrate told Transform Justice: ‘I’ve felt for a long time that there is a hidden agenda in the civil service to get rid of the lay magistracy. We are seeing more and more district judges being appointed and taking over a lot of the work we used to do.’

Summary non-motoring cases cost an average of £18 to conduct by magistrates and £55 by district judges. District judges are also more likely to use custody than lay magistrates, costing more to the criminal justice system, said the charity.

Transform Justice, founded in 2012 by a former magistrate is calling for an ‘open debate about the future of the judiciary in the magistrates’ courts’.

The government last year outlined plans to give greater powers to the magistracy.