Tougher prison sentences reduce crime, particularly burglary, according to ground-breaking research.

The study, by academics at Birmingham University, also found that during periods when police detect more offences, crime tends to fall overall, suggesting that levels of police activity – and therefore of staffing – have a direct impact on criminal activity.

The findings are likely to be seized on by critics of the government's plans for reducing the number of police officers as part of spending cuts.

The research, carried out for Civitas, an independent thinktank, used local sentencing data released by the Ministry of Justice under freedom of information requests to track the effectiveness of penal policy and policing on recorded crime across the 43 forces in England and Wales between 1993 and 2008.

The researchers concluded that prison was particularly effective in reducing property crime when targeted at serious and repeat offenders. They concluded that an increase of just one month in the average sentence length for burglaries – from 15.4 to 16.4 months – would reduce burglaries in the following year by 4,800, out of an annual total of 962,700.

For fraud, an increase in sentences from 9.7 to 10.7 months would result in a reduction of 4,700 offences a year, out of 242,400. The report declares this to be "a substantial effect, especially when we consider that the length of sentence usually corresponds to approximately half the actual time spent in custody".

The study also estimates that a policy of forcing offenders to serve a higher proportion of their sentences in prison would have a further dramatic effect on cutting crime, in part because more offenders would be behind bars for longer. If offenders were made to serve two-thirds of their sentence in custody, rather than the current half, it suggests that there would be 21,000 fewer recorded burglaries and 11,000 fewer recorded frauds in England and Wales.

The findings tend to support the thrust of policies followed by the last Labour government, which increased funding to the police and concentrated on the roughly 100,000 persistent offenders responsible for a high proportion of crime. This approach increased the prison population, but it also led to reductions in overall levels of crime.

By contrast, the current justice secretary, Kenneth Clarke, often questions the relationship between criminal justice policy and the level of crime and suggests that economic factors may be just as, if not more, important. Clarke has been involved in a long-running dispute with one of his Tory predecessors, Michael Howard, whose mantra that "prison works" became associated with his time at the Home Office.

In 2010 Clarke questioned whether tough penal policy cut crime: "No one can prove cause and effect. The crime rate fell [under Labour], but was this the consequence of the policies of my successors as home secretary or, dare I gently hint, mine as chancellor of the exchequer at the beginning of a period of growth and strong employment? We will never know."

The report says there is "unequivocal" evidence that more sustained and effective policing cuts crime. "More detection is associated with substantial reductions in crime. It plays a sustained role in preventing crime," says the study, which found that a 1% increase in the detection rate would prevent 26,000 burglaries, 85,000 thefts, 2,500 robberies and 1,800 frauds a year.

However, the director of campaigns at the Howard League for Penal Reform, Andrew Neilson, questioned the claims.

"The effect of prison on reducing crime has never been proven and this research falls short of doing so," Neilson said. "There are numerous international examples of jurisdictions which have experienced both falls in crime and falls in prison numbers.

"Research by the last government supports claims made since by Kenneth Clarke that factors such as a benign economy and improved home security had greater roles to play in the fall in crime in England and Wales than an increase in the use of imprisonment."

Neilson also said that the research ignores the "clear failure of prison as spelled out in reoffending rates". He added: "Lengthening prison sentences at additional cost when prisons are already failing will not provide lasting solutions to crime."

"Acquisitive Crime: Imprisonment, Detection and Social Factors" will be published at civitas.org.uk on Monday