Scrapping the right to a jury trial for lesser offences that "clog up the courts" could save £30 million a year in prosecutors' costs alone, the Government's victims' commissioner said today.
Louise Casey said almost 70,000 cases which could be heard by magistrates were making up more than 40% of the crown court's business every year, causing greater expense and leading to long delays for victims and witnesses of more serious offences.
And nearly two-thirds of defendants who opt to be tried in the crown court go on to plead guilty, leaving the taxpayer to pick up millions of pounds each year in costs, she said.
"If just half of the 'either way' cases which currently end up in the crown court could be kept in the magistrates' courts, we could be saving £30 million a year in CPS case preparation costs alone," she said.
"We should not view the right to a jury trial as being so sacrosanct that its exercise should be at the cost of victims of serious crimes.
"Defendants should not have the right to choose to be tried by a jury over something such as the theft of a bicycle or stealing from a parking meter."
She said serious crimes were being "stacked up waiting for court time" while defendants charged with such offences as the theft of tea bags and biscuits worth £24 were opting for crown court trials.
"This cannot be right," she said.
Ms Casey added that victims and their families suffered "when crown courts are clogged up".
"It is known that waiting for a criminal trial often means that victims put their lives on hold; bereaved families of murder victims cannot grieve until the trial is over," she said.
"It is hard to look victims in the eye and say we must spend money preserving sacred cows such as trial by jury for petty offences when, for example, victims of child abuse are not getting dedicated help in court, or families of loved ones murdered are waiting years to see justice done."
Victims currently have an average waiting time of 28 weeks for a crown court trial, with this often reaching a year in London, she said.
"Some victims may decide to give up on the trial ever being heard, deciding they cannot keep their lives on hold indefinitely, and may no longer be willing to testify in court.
"And the longer the period between the crime and the trial, the less reliable that witness's evidence is likely to be regarded. Is this a gamble that some defendants take?
"This is not justice."
Ms Casey also backed calls for magistrates' sentencing powers to be increased to one year so they can avoid referring more cases to the crown court.
The average daily cost of running a trial in the magistrates' courts is £800, compared with more than double that, £1,700 in crown courts, she said.
Ms Casey also criticised defendants who "hold out to see if witnesses turn up" before pleading guilty at the last minute.
"That is not justice; it is a publicly funded waiting game," she said.
"It is an abuse of the system, and puts an intolerable pressure on victims and witnesses that could be called a form of witness intimidation.
"We need to stop the abuse of the process which allows defendants and their solicitors to string out a case at the expense of victims and the public."
Defendants who changed their plea to guilty on the first day of the trial wasted around £15 million annually in case preparation costs, she said.
Last month, Keir Starmer QC, the Director of Public Prosecutions, said a shake-up of the criminal justice system was needed as it emerged that almost half of cases do not proceed to trial.
"This is a system that cannot afford to run any more," he said.
Calling for a system of early guilty pleas that would require defendants to admit their guilt at their first court hearing in return for a discount in sentence, he said: "If we are preparing one in every two cases unnecessarily, then 50% of our work is being done unnecessarily."
A Ministry of Justice spokesman said: "We are considering how best to encourage guilty pleas at an earlier stage, while preserving a person's long-standing right to have their case heard before a jury.
"We are committed to ensuring that every victim can access the support they need to help cope with the consequences of crime, and we are working to improve the help available during the investigation and court hearings process."
Javed Khan, chief executive of Victim Support, said trials which were postponed or delayed at the last minute were "not only a waste to the taxpayer but also highly distressing for witnesses and victims who have emotionally prepared themselves for court".
"Most critically, this damages their confidence in the criminal justice system as a whole," he said.
"Victims and witnesses want justice to be done and be done swiftly so that they can move on with their lives."