The government has overstated its successes on law and order since 1997, a study has claimed.
Police numbers have been increased
Billions spent on reform has brought no major improvement, the Centre for Crime and Justice Studies says.
The study's authors accused ministers of setting easy targets and taking credit for crime reduction trends unconnected to their policies.
The Home Office said the analysis was wrong and pointed to record numbers of police officers and prison places.
In a separate development, the Association of Chief Police Officers (Acpo) is warning that the police are not getting enough funding from central government.
A 3.6% rise in funding is promised this year - but Acpo say they will be getting lower increases over the following three years.
The Centre for Crime and Justice Studies (CCJS) report, funded by the Sunday Times and the Hadley Trust, pointed out that the number of convictions had actually fallen since the late 1990s.
The report's co-author Richard Garside, of King's College in London, told BBC Radio 4's Today programme: "What we have seen is a massive expansion of non-conviction offences brought to justice."
These included "things like cautions, penalty notices and other administrative means of hitting targets", he said.
He conceded there were now fewer burglaries and less car crime, but said this was more to do with improvements in security systems than government policy.
The report found that the government had hit many of its targets - the official crime rate falling by 35% since 1997, and a 15% reduction in crime in the five years to 2007-2008.
But the study said the UK now spent more on law and order than any other country in the EU - as a proportion of its overall spending - yet the number of killings and robberies was still rising.
And one of the government's "most conspicuous failures" was on reoffending - with targets being modified, missed or dropped.
"On paper, nearly all the targets have been met," the study said.
"In reality, Labour's record on its various overall crime reduction targets is at best mixed; at worst, its crime reduction claims are misleading."
Shadow home secretary David Davis said the report "betrays a history of fiddled figures and doubtful claims".
He said falling conviction rates combined with increases in the use of fines and cautions meant "actual and effective justice is not being delivered".
But the Home Office said it "firmly rejected" the report's claims, saying the governed had made "good progress in building a safer Britain since 1997".
"Over 250,000 more offences are now brought to justice each year than five years ago through a range of punishments," a spokeswoman said.
She added that punishments such as penalty notices for disorder saved thousands of hours of police time.