When in trouble it’s often said it is best to get a good lawyer.

That’s what the City and County of Honolulu appears to have done in hiring a San Francisco law firm that charges $700 an hour. Even before the contract was signed, the City Council had already approved paying $150,000.

That figure could easily grow exponentially by the time the work of Farella Braun & Martel concludes three years from now. If it concludes.

There’s just one very serious problem: City officials won’t tell the people who are footing the bill — us, the taxpayers of Oahu — exactly what all the money is for.

But it must. Such secrecy over such a major expenditure at the top levels of city governance is simply unacceptable.

And the way the city has gone about authorizing the law firm’s service — in closed session, and with evasive and vague public disclosure only when pushed by Civil Beat — falls woefully short of the standards and practices that are to be expected.

If Honolulu was a metropolis less plagued by corruption it might be easier to surmise what the feds are looking into. But there are just too many possibilities, starting with the disgraceful Kealoha saga and rail project mess.

This we do know: The legal work is tied to “ongoing federal criminal prosecutions” — information that comes not from the city but Farella Braun & Martel’s website.

As Civil Beat reported late last month, it involves trying to keep secret numerous government documents including emails seized by the feds at the beginning of the year. There is fear that attorney-client privilege could be violated should the information be disclosed to prosecutors.

That, said City Councilman Ron Menor, is privileged information, even though he did not say who the emails came from, what departments are involved nor the time frame in which they were sent and received.

Andrew Pereira, Mayor Kirk Caldwell’s communications director, said city attorneys could not discuss the matter, either — even though he did not identify the city law that requires the corporation counsel’s office to stay mum.

Menor and Caldwell — both attorneys — and the colleagues who support this dubious position do not seem to appreciate that the client in this legal matter is actually the people of Honolulu.

We understand that officials sometimes require legal representation in the course of their duties. It’s possible that city attorneys may have a conflict of interest, thus requiring outside hires.

But we have a fundamental right to know much more than we’ve been told. The fact that Menor could not even name the federal judge who is reviewing the material in question is shocking.

Councilmember Kymberly Pine, a candidate for mayor next year, has it right when she said Caldwell should tell the public exactly why the firm was hired and what records were seized.

“To restore trust with the public, we should just be honest about everything that’s going on,” she said.