^ This is CORRECT… you HAVE to be part of the conversation to be recording, you would not need the second parties consent, and they would not even need to know the conversation is being recorded. This would be fully admissible in court. How do I know this? I’ve sat in on MANY court cases, formally studied in various aspect of the law, also had actual detectives (the guys that actually deal with real crime and not hand out bullshit tickets) as instructors not your run of the mill police constables.
However if you placed a recording device in a room, area or recording someone else’s phone conversations which you are not part of (your not actually speaking or anything) even if the topic is about you but you are not directly speaking. The recording will not be admissible in court.
This is generally the rule for non law enforcement regarding recordings and video.