The Edgartown police department has achieved accreditation status from the Massachusetts Police Accreditation Commission, police chief Bruce McNamee announced last week.

Accreditation is the second tier of two benchmarks set by the agency, which is made up of more than 200 participating departments. To achieve the status, a police department has to fulfill more than 257 standards and be reviewed by visiting accreditation representatives.

Chief McNamee said the achievement was a group effort that began under the leadership of former chief David Rossi. He thanked Lieut. Chris Dolby and administrative assistant Maria Ventura for leading the renewed accreditation effort. He said the department had also received guidance from officers in Oak Bluffs and in West Tisbury, which was the first department on the Island to achieve the status.

Much of the process is administrative: putting policies in writing, documenting practices and creating checklists.

“How do you handle money, how do you handle internal security, computer security,” Chief McNamee said, citing examples. “It makes you become introspective: are you doing things the proper way.”

Accreditation lasts for three years, at which point the department will have to be reviewed again.

“Keeping it is as important as attaining it,” the chief said.