Labour's controversial court reforms were branded a 'soft justice surrender' as it emerged they will lead to fewer offenders being jailed.
Justice Secretary David Lammy published new legislation which will strip thousands of defendants a year of the historic right to jury trial.
Cases will instead be heard by a judge sitting alone in a bid to reduce the Crown court backlog - currently at a record 80,000 and set to hit 100,000 in just a year's time.
But in a dramatic development it was confirmed Labour's reforms will also lead to a fall in the number of criminals in jail.
Official Ministry of Justice documents published on Wednesday showed that following an initial spike in the prison population the changes would see fewer offenders behind bars.
Government research also showed that where similar judge-only trials have been introduced in other parts of the world it led to more defendants being acquitted and to shorter jail sentences being handed down.
Shadow Home Secretary Chris Philp said: 'This is a soft justice surrender from this weak Government who have already let criminals out of jail early and cut police numbers.
'Their own figures show fewer people will end up in prison, which means the public will be endangered.
Justice Secretary David Lammy launched his plans to limit jury trial this week
'We need to crack down on criminals rather than simply be soft touch.'
Shadow Justice Secretary Nick Timothy said the new disclosures showed Labour were a 'party of lefty human rights lawyers' who 'cannot be trusted with public safety'.
'Now we know the reality of their plans is to send even fewer people to prison in future,' he added.
Ministers said earlier this week they expect judge-only trials to be introduced in 2028, assuming the legislation overcomes opposition from backbench Labour MPs and the House of Lords.
Official documents published alongside Mr Lammy's new Courts and Tribunals Bill showed there would be a short-term increase in the jail population while the backlog is cleared, peaking at 900 extra inmates in 2033.
But after that it would lead to a 'gradual decline' in the number of offenders in prison, leading to a 'lower overall prison population'.
'We expect criminal court reform to reduce the prison population relative to the baseline,' it said.
Another document published with the Bill said research carried out in 2024 into judge-only trials in New South Wales showed they led to more defendants being acquitted, possibly because judges applied a higher threshold for evidence than juries.
The Australian research also showed judge-only trials resulted in a lower likelihood of a convicted criminal being handed jail and, if they were imprisoned, sentences were shorter than for those who had a jury trial.
People spray sparkling wine over a man who walked out of Nottingham Prison on September 10, 2024 - the day Labour's existing early release scheme came into effect
On the first day of Labour's scheme in September 2024, lags released early were seen celebrating outside jails. Pictured: A man celebrates as he is released from HMP Wandsworth
The paper said there was 'no directly comparable data set to estimate how conviction rates may differ in trial without jury in the Crown Court'.
But once a judge-only trial has been introduced in England and Wales officials would 'regularly review the data … to obtain an up-to-date understanding of the impact of reforms'.
The documents also showed that the reforms will cost £338million to implement over 10 years.
Labour has already released nearly 50,000 prisoners early and passed legislation that will allow inmates to be freed from jail at an earlier point.
Mr Lammy, who is also Deputy Prime Minister, said: 'The criminal courts we inherited were on the brink of collapse, with victims waiting years for justice while the backlog spiralled out of control.
'Our courts reform will deliver record investment, serious reform and practical modernisation to get cases heard faster, protect jury trials for the most serious crimes, and set us on a path to turn the corner on the rising backlog by the end of this parliament.'
