No two police forces are the same and no two police budgets are the same. A large police budget could indicate that there is a serious crime problem in an area or it could show that crime is under control.
Different cities and different states will have different targets and priorities for their budgets. Some areas may have major problems with domestic crime while others have issues with motoring offenses or industrial crimes. The problems and issues in an area will have to be assessed before a budget is set dealing with priority crimes.
Even within a state or city there will be different patterns and needs for the police budget. Inner city areas tend to be where crime is most common and will require most resources. There are a wide range of crimes that go on in inner city areas and that is why resources are likely to be concentrated in these areas.
Auditing the value obtained from a police budget is an important aspect of the job. Keeping tabs on the returns for expenditure allows accurate evaluations to be made and to ensure that resources aren't being wasted when they could be better deployed elsewhere. Police forces have to keep certain reserves and have contingency plans for special events. When a major incident or disaster occurs they must have access to the resources needed immediately- there would be an outcry if time was lost or negotiating had to be carried out to free up funds for certain needs.
Comparisons will always be made between police forces to establish what value for money is being obtained, if there are wide discrepancies the matter would have to be looked into as to why one force is getting a better return than another after factoring out local issues.