This week, the number of officially accredited police departments in the country should more than double. And while the idea of giving such departments a nationally recognized stamp of approval is still new, solid business reasons seem to assure that the number of departments involved in the process will grow rapidly.

So far, five police departments have been certified by the Commission on Accreditation for Law Enforcement Agencies: Baltimore County, Arlington County (Virginia), Elkhart County (Indiana), North Providence, R.I., and tiny Mount Dora, Fla., with a police force of 17. But at a meeting later this week, the commission is expected to okay applications from seven more departments, including Fairfax County and Tampa and St. Petersburg. Big cities, including Chicago, Boston and Houston, also are moving towards accreditation.

Accreditation doesn't make a police force any more legal: An arrest by an unaccredited police force is just as valid as an arrest in Mount Dora. But accreditation may well help a local government when it comes to controlling expenditures. Litigation against police forces is a growing expense, and commercial insurance companies that cover such contingencies are leaving the market in droves. Accreditation may help turn that trend around.

One broker who specializes in insuring law enforcement agencies is offering a 10 percent premium reduction to clients who are going through the accreditation process, and at least two other insurers are subtracting from their premium costs the accreditation fees, which can run up to $14,700.

The commission has no official standing -- it was begun with federal money, but is careful to keep its distance from the Washington bureaucracies. It is now being supported by foundation grants -- and the hefty accreditation fees. But the commission is made up of a wide enough spectrum of the law enforcement community and its watchdogs -- including the Chief Justice of Colorado and a Brandeis University sociology professor -- that it has managed to represent a concensus position.

"The insurance industry is interested in police departments' not having lawsuits, and anything that would contribute to their not having lawsuits is a plus," says Natalie Wasserman, executive director of the Public Risk and Insurance Management Association. "Anything that police departments can do to tighten up their organization and structure is certainly going to be to their advantage as far as the insurance industry is concerned."

Tightening up is just what a department must do to win accreditation. The commission lists 944 standards, and a department must comply with most of them to be recognized. But in most cases, the commission doesn't tell the department how it must handle a controversial issue; the commission only requires that the department issue a policy statement well in advance of any problem.

For instance, in most cities, it is common for officers to learn the limits of their job from supervisors, training sessions, and, perhaps, from a manual. The commission requires a department to pull together those random bits of information in a single written document spelling out the limits of discretion. It is up to each department, however, to set its own rules. Similarly, the commission takes no stand on whether off-duty officers should carry arms, but does require a written policy answering the question.

The standards cover more than public safety. They demand a written directive on promotion policies and a procedure for auditing the department's books. Other standards are keyed to the size of the department. Big forces, for example, are told they must have a planning and research operation, while for middle-size departments, the standard is optional; it is considered inapplicable to police forces of fewer than 50 persons.

By the time a department goes through the accreditation process, it should have gotten its act together and should make fewer of the kind of mistakes that give rise to citizen suits. But the litigation impact goes beyond that. The mere fact that a department has been nationally recognized for its high standards may scare off would-be plaintiffs, and may help a department sway a jury when cases are filed. Many suits against police departments allege that the officials violated a citizen's civil rights, and having written policies in place may help convince jurors that if an officer made a mistake, it does not represent department policy.

The very standards that win accreditation can be double-edged, however, if the department is sued because a police officer's warning shot hit a passerby. The arguments will be over what the proper conduct should have been, and, warns Wasserman, "if there are procedures and they're not being followed, then you really are in trouble."