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I'm sorry to hear about your situation. No, it's not legal. The statutory law states that all parties need to consent to an in party conversation:
Oregon Revised Statute § 165.540¹ :Obtaining contents of communications
(1) Except as otherwise provided in ORS 133.724 (Order for interception of communications) or 133.726 (Interception of oral communication without order) or subsections (2) to (7) of this section, a person may not:
(a) Obtain or attempt to obtain the whole or any part of a telecommunication or a radio communication to which the person is not a participant, by means of any device, contrivance, machine or apparatus, whether electrical, mechanical, manual or otherwise, unless consent is given by at least one participant.
(b) Tamper with the wires, connections, boxes, fuses, circuits, lines or any other equipment or facilities of a telecommunication or radio communication company over which messages are transmitted, with the intent to obtain unlawfully the contents of a telecommunication or radio communication to which the person is not a participant.
(c) Obtain or attempt to obtain the whole or any part of a conversation by means of any device, contrivance, machine or apparatus, whether electrical, mechanical, manual or otherwise, if not all participants in the conversation are specifically informed that their conversation is being obtained.
(d) Obtain the whole or any part of a conversation, telecommunication or radio communication from any person, while knowing or having good reason to believe that the conversation, telecommunication or radio communication was initially obtained in a manner prohibited by this section.
(e) Use or attempt to use, or divulge to others, any conversation, telecommunication or radio communication obtained by any means prohibited by this section.
(2)(a) The prohibitions in subsection (1)(a), (b) and (c) of this section do not apply to:
(A) Officers, employees or agents of a telecommunication or radio communication company who perform the acts prohibited by subsection (1)(a), (b) and (c) of this section for the purpose of construction, maintenance or conducting of their telecommunication or radio communication service, facilities or equipment.
(B) Public officials in charge of and at jails, police premises, sheriffs offices, Department of Corrections institutions and other penal or correctional institutions, except as to communications or conversations between an attorney and the client of the attorney.
(b) Officers, employees or agents of a telecommunication or radio communication company who obtain information under paragraph (a) of this subsection may not use or attempt to use, or divulge to others, the information except for the purpose of construction, maintenance, or conducting of their telecommunication or radio communication service, facilities or equipment.
(3) The prohibitions in subsection (1)(a), (b) or (c) of this section do not apply to subscribers or members of their family who perform the acts prohibited in subsection (1) of this section in their homes.
(4) The prohibitions in subsection (1)(a) of this section do not apply to the receiving or obtaining of the contents of any radio or television broadcast transmitted for the use of the general public.
(5) The prohibitions in subsection (1)(c) of this section do not apply to:
(a) A person who records a conversation during a felony that endangers human life;
(b) A person who records a conversation in which a law enforcement officer is a participant, if:
(A) The recording is made while the officer is performing official duties;
(B) The recording is made openly and in plain view of the participants in the conversation;
(C) The conversation being recorded is audible to the person by normal unaided hearing; and
(D) The person is in a place where the person lawfully may be;
(c) A person who, pursuant to ORS 133.400 (Recording of custodial interviews), records an interview conducted by a peace officer in a law enforcement facility;
(d) A law enforcement officer who is in uniform and displaying a badge and who is operating:
(A) A vehicle-mounted video camera that records the scene in front of, within or surrounding a police vehicle, unless the officer has reasonable opportunity to inform participants in the conversation that the conversation is being obtained; or
(B) A video camera worn upon the officers person that records the officers interactions with members of the public while the officer is on duty, unless:
(i) The officer has an opportunity to announce at the beginning of the interaction that the conversation is being obtained; and
(ii) The announcement can be accomplished without causing jeopardy to the officer or any other person and without unreasonably impairing a criminal investigation; or
(e) A law enforcement officer who, acting in the officers official capacity, deploys an Electro-Muscular Disruption Technology device that contains a built-in monitoring system capable of recording audio or video, for the duration of that deployment.
(6) The prohibitions in subsection (1)(c) of this section do not apply to persons who intercept or attempt to intercept with an unconcealed recording device the oral communications that are part of any of the following proceedings:
(a) Public or semipublic meetings such as hearings before governmental or quasi-governmental bodies, trials, press conferences, public speeches, rallies and sporting or other events;
(b) Regularly scheduled classes or similar educational activities in public or private institutions; or
(c) Private meetings or conferences if all others involved knew or reasonably should have known that the recording was being made.
(7) The prohibitions in subsection (1)(a), (c), (d) and (e) of this section do not apply to any:
(a) Radio communication that is transmitted by a station operating on an authorized frequency within the amateur or citizens bands; or
(b) Person who intercepts a radio communication that is transmitted by any governmental, law enforcement, civil defense or public safety communications system, including police and fire, readily accessible to the general public provided that the interception is not for purposes of illegal activity.
(8) Violation of subsection (1) or (2)(b) of this section is a Class A misdemeanor.
(9) The exception described in subsection (5)(b) of this section does not authorize the person recording the law enforcement officer to engage in criminal trespass as described in ORS 164.243 (Criminal trespass in the second degree by a guest), 164.245 (Criminal trespass in the second degree), 164.255 (Criminal trespass in the first degree), 164.265 (Criminal trespass while in possession of a firearm) or 164.278 (Criminal trespass at a sports event) or to interfere with a peace officer as described in ORS 162.247 (Interfering with a peace officer or parole and probation officer).
(10) As used in this section:
(a) Electro-Muscular Disruption Technology device means a device that uses a high-voltage, low power charge of electricity to induce involuntary muscle contractions intended to cause temporary incapacitation. Electro-Muscular Disruption Technology device includes devices commonly known as tasers.
(b) Law enforcement officer has the meaning given that term in ORS 133.726 (Interception of oral communication without order). [1955 c.675 §§2,7; 1959 c.681 §2; 1961 c.460 §1; 1979 c.744 §9; 1983 c.693 §1; 1983 c.740 §35; 1983 c.824 §1; 1987 c.320 §87; 1989 c.983 §14a; 1989 c.1078 §1; 2001 c.104 §54; 2001 c.385 §4; 2003 c.14 §62; 2007 c.879 §1; 2009 c.488 §2; 2015 c.550 §2; 2015 c.553 §1]
So in short, it would be illegal to record a conversation (even one where threats were being made) if you did not inform the other person of the recording. But if it's a situation where the conversation is in a public venue, where there's no reasonable expectation of privacy, then you can still record it. For example, if you're at a restaurant (rather than in your home, etc...) then there's no expectation of privacy in that conversation, where it's reasonable that someone would hear the conversation.
Hope that clears things up a bit. If you have any other questions, please let me know. If not, and you have not yet, please rate my answer AND press the "submit" button, if applicable.
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