A study into the mooted amalgamation of the Tisbury and Oak Bluffs police departments has concluded that a merger would produce a better standard of policing and could save the towns close to $500,000 a year.

The MMA Consulting Group report, delivered to the towns this week, looked at options for greater cooperation between the towns’ police departments, ranging from limited sharing of some services to full amalgamation. It recommended amalgamation.

As things currently stand, the report says, there is unnecessary “duplication of administrative systems, command positions and investigative services” in the two departments.

The forces were top heavy, with two chiefs, two lieutenants and two detectives, yet they lacked sufficient middle-ranking officers to ensure proper supervision.

And this was costly. Collectively, Tisbury and Oak Bluffs spend around $3 million each year on their forces, not including health and retirement costs.

Between them, the police departments now have 29 full-time police officers — 15 in Oak Bluffs and 14 in Tisbury — and three administrative employees.

The report proposes a reduction of six or seven staff — five or six police and one administrative worker — to make for a consolidated force of one chief, one lieutenant, four or five sergeants, one detective and 16 officers.

This would make redundant the positions of one chief, one lieutenant, two officers and maybe one sergeant, making for a better balance of ranks which provided “sufficient supervisory personnel.”

The towns’ saving in wages alone would amount to an estimated $362,000 if the police numbers were cut by six, or $479,200 if they were cut by seven, the seventh being a sergeant.

There would be other savings too, in administrative and operating costs. Two police cars and two other vehicles could go.

“Assuming that the departments consolidate, their facilities should be integrated. The Tisbury police station has limited parking and most police activity occurs on the second floor,” the report says.

“Consolidation would enable the towns to centralize many functions, especially patrol functions, at the Oak Bluffs police station. The Tisbury facility could be used for support functions.”

The report includes a detailed breakdown of the task of the forces, from the length of road they have to patrol to the types of crimes each force must deal with, and how much police time various incident types should take.

The forces, the report says, serve a year-round population of fewer than 8,000 people, and a seasonal population of some 47,000. They receive about 9,500 calls for service each year. There are some 2,400 incidents requiring police action in Oak Bluffs and 1,300 incidents in Tisbury each year on average.

Even with a reduced total force, the report says, there would be “sufficient patrol resources ... to absorb a substantial increase in the demand for service.”

Force numbers would be reduced through attrition, the report says, and notes that already Tisbury is short one officer and one lieutenant.

The MMA report recommends that the towns implement the merger via an intermunicipal agreement, an arrangement which might prove problematic, given the independence of Vineyard towns and the fact that under such an agreement, one town becomes the agency responsible for the force.

“As a practical matter,” the report says, “one town would have to be the employer and assume responsibility for managing employee benefits and services. The town should be compensated for the administrative work and the risk that is assumed.”

But, it says, both towns would have equal input via a five or seven-member oversight committee, including the town administrator of each town.

There also is the problem of apportioning costs. The report canvassed several cost allocation models, involving factors including equalized property valuations of the towns, resident population, the number of calls for service and the respective crime rates.

When the report’s authors ran the numbers under a couple of different allocation models, the results showed almost all the savings from a merged force accrued to Oak Bluffs.

Under one model, Oak Bluffs was better off by more than $360,000, while Tisbury actually incurred $700 in extra costs.

The critical factor, then, in whether the amalgamation plan goes forward is likely to be the attitude of Tisbury selectmen.

Yesterday, the chairman of the Tisbury board, Jeff Kristal, was determinedly noncommittal.

“We’re focused now on town meeting. After that is past, we’ll have the time to go deeper into this,” he said.

Mr. Kristal went on to point out that the town still is waiting for another report on the financial viability of a possible merger, from the state Department of Revenue.

Selectman Tristan Israel was more openly skeptical of the report.

He questioned its methodology, and noted some issues not canvassed in it, such as the fact that the two departments operate on different pay scales.

“I still have some serious questions,” he said. To me the bottom line is there has to be a significant financial saving for Tisbury.”

The most positive was Geoghan Coogan, although he also said he was reserving judgment until after there had been more discussion and the DOR report was received.

“In a broad sense everything in there makes sense to me,” he said of the report.

“The one surprise was the recommendation that we use an intermunicipal agreement as the vehicle. Our original take on that was that one town would essentially disappear, and the entire budget process has to go through one town. You’d lose your identity.

“From reading the report, though, it seems that may not be entirely true. Both towns would have oversight.”

He acknowledged a merger might not give Tisbury any immediate financial benefit, “and maybe not even much long-term benefit.”

But there was more to consider than just money; there was also the question of whether a merger would make for operationally better policing.

And the report seemed clear on that, he said.