There is no one-size-fits-all format for a civilian agency that polices the police, a national expert says.

"We aren't in a position to say what's the most effective model," Brian Buchner, president of the National Association for Civilian Oversight of Law Enforcement, said in an interview.

Each community should tailor a civilian review board to meet its own goals, said Buchner, a special investigator with the Los Angeles Board of Police Commissioners Office of the Inspector General.

On Monday night, Buchner told a Community and Local Law Enforcement Task Force subcommittee there are more than 200 civilian oversight entities in the United States and "no two are exactly alike."

The Sonoma County Law Enforcement Accountability Subcommittee is charged with developing a model for an independent civilian review board that would investigate officer-involved shootings.

Review boards are "a very real and concrete way" to involve citizens in police oversight, covering such issues as use of force, complaints of misconduct and setting department policy, Buchner said

Sonoma County's consideration of a civilian review board was prompted by the fatal shooting of 13-year-old Andy Lopez by a sheriff's deputy last fall, and Buchner said the impetus can come from a single event or a series of critical incidents.

In developing a review board, Buchner said it is important to involve citizens, community leaders and law enforcement. "Everyone needs to have a seat at the table," he said.

Subcommittee member Eric Koenigshofer, a former county supervisor, asked whether review board investigations should be conducted by professionals rather than lay people.

"That's a debate that goes on," Buchner said. "It really just takes someone with an analytical eye."

But a review board "can be perceived differently by law enforcement" if it has experienced investigators, he said.

Subpoena power to compel testimony and obtain records is important, he said, "but oversight can be effective without it."

Civilian oversight dates back to the civil rights movement of the 1960s, largely in response to black communities that were demanding an end to discrimination and abuse by police, Buchner said in the interview.

Now the goal is to more broadly assure that police abide by the law and to establish a transparent process for assuring good conduct.

"Openness is indispensable," Buchner said.

Some communities want a review board membership that reflects the area's racial diversity, while others want members with expertise, such as law enforcement.

"There's no reason why you can't do both," he said.