From time to time, clients discover their spouse or partner is recording their phone calls. The first question is usually, "Isn't that a crime?!"
In many states it is, in fact, a crime to record phone conversations. Oregon, however, is known as a "one-party consent" state. That is, if one party consents to the recording, it is lawful to record all or part of the conversation. For practical purposes, this means as long as the person making the recording consents, the recording is legal.
Note that the law is clear that an individual cannot use a device or machine to record a conversation unless all parties of the conversation are explicitly informed that their conversation is being recorded.