Disregarding any criminal laws, Koch can certainly sue for defamation. And should.
Applicable recording laws from Wikipedia (and sources cited in Wikipedia)
http://en.wikipedia.org/wiki/Telephone_recording_laws
So if the call originated by one of the 2-party states listed above, than a criminal law was broken.
However, there may even be identity theft criminal charges that can be considered, particular if a cell or internet phone were used.
This is a bag of worms.
I have not listened to the Court TV programs --Judge Judy etc.-- in Years, however I do remember a couple of cases she had that involved phone conversations in California.
One involved a case where the defendant taped a phone conversation without the knowledge of the caller--that case ruled that the Judge could not allow the tape to be used or listened to.
Another case where the caller left a message on a answering device was allowed.
This leads to the question of do people have the right to tape record conversations in ones own home without telling a visitor.
VA> back in the 1970 in cases involving the Child Protection Agency was turned on its head when Parents felt they needed proof of in compent workers took to recording the conversations of the workers when they came to their home. Phone conversations recorded and in fact investigated the investigates. Big turn over in workers for that Agency, much embarrassing things came to light.
When someone calls you on the phone are they not just in fact within your home as if they were in the street with a bull horn.
Now to stolen identity, to call or visit and misrepresent your self as a person with power, say a police officer, the Mayor or who ever and record the conversation under the name of or position of someone is Identity theft. The person who had their name stolen needs to put the hammer down on whoever used their name for their own benefit.
Rant here , question: Why did the Governor not have his incoming calls taped himself. Tapes can be edited and without a tape by the Governor to expose or counter what he did or not say------We have to remember Rosemarie Woods that accidentally lost some tapes in the days of Nixon.