SEATTLE - When it comes to answering the most urgent calls, Seattle Police set a goal -- responding within 7 minutes, at least 90 percent of the time.

Currently, the department is in the 11 to 14 minute range.

So what would it take to make that happen?

"It seems very intuitive, how many cops do you need at the department?" Maxey said to the Seattle City Council.

A simple question with a not so simple answer.

The long awaited Berkshire report compared Seattle to 11 other police departments.

The report concluded that the SPD needs to add 175 officers, along with adding 107 full time equivalents (F.T.E.'s) in overtime.

The mayor already set the goal of hiring 200 officers by 2019. But SPD admits that number may fall short.

"We know we're going to add the net 200 by 2019, will that be enough?," said Maxey. "I don't know. We're going to need to develop a more sophisticated model based on Berkshire advisors report, take it further, look at other analytics and assess on the way. It may be we get to 2019 and say we're not there yet."

According to Maxey, the study has its limits. It's based on a snapshot in time -- staffing levels in June of 2015. And comparing Seattle to other cities doesn't always line up.

"It's not a perfect mesh with Seattle because we do have unique priorities and we do things differently here," he said.

But the council pointed out Berkshire offers an alternative scenario: hiring 32 fewer officers if the department uses civilians to respond to some non-emergency calls.

"A, we'll save money there," said Councilmember Tim Burgess. "And B, it'll give us much greater flexibility to respond to the needs of the community."

Such a change would need to pass labor negotiations.

An earlier draft of the study asked for 343 officers. And there have been accusations that SPD didn't like the results and sent it back.

Maxey explained that in the earlier draft, Berkshire didn't realize that SPD already takes attrition into its hiring practices, and that's why the final report is more accurate.