It is unrealistic to expect the police to act as the sole deterrent to criminal behaviour. The majority of police work concerns the detection rather than the prevention of crime. Only a massive and unfeasible expansion of police numbers and powers could provide a real deterrent to criminality.  The purpose of deterrence is to reduce the likelihood of damaging behaviour without dramatically raising the cost of enforcing the law. Deterrence relies on individuals acting in a rational manner and being able to regulate their own behaviour. Property crime often results from the offender performing a rational balancing of his likely gains against the likely costs of incarceration. Limiting the use of prison sentences means that calculating offenders will be much more likely to engage in property crime.  Finally, the proposition is unable to deal with the threat posed by habitual and compulsive petty criminals. The actions of such individuals often straddle the boundary between outright criminality and anti-social behaviour. Their offences may never be severe enough to attract a penal sentence, but it is the continuous and repeated nature of their criminal acts that causes harm. Once again, the best response to such conduct is the forcible segregation of the offender inside a prison.