Hmmm, Sherwood - very interesting topic! One I've had to write government policy on
I couldn't begin to comment on the US, nor any other country suffice to say that there are increasing rules and protocols (rightly) being legislated everwhere. Since 9/11 (and other events) there is an increasing tollerance to the use of recording devices to prevent terrorism - but at the expense of some civil liberties.
In Australia it is lawful to record a conversation you are a party to. That is, if you are involved in the conversation (being present and using non verbal language included) then you have a right to record the conversation for accuracy. You do not have to tell any person - however if you are a police officer and consider that you may use the conversation as evidence in court, you must warn the other parties that the conversation is being recorded. Unless you have a "monitoring warrant" which means you can record away to your heart's content!
I know it may seem draconian, but there are times that it is appropriate to record certain conversation in the workplace. I call it C.A.R.E
Cover
Arse/Ass
Retain
Employment
It is very hard to dispute what was said when it is recorded... that includes the voice inflections and implied tones that a written record cannot reflect.