You have not indicated what kind of recording is involved here. Recording a telephone conversation to which you are not a party is "wire-tapping" and illegal without a court-issued warrant. Recording a telephone conversation to which you are a party is illegal in certain states, called the "two-party" states. A list of such states that may be reliable is the wiki "telephone recording laws." If you mean a recording of a personal conversation the rules are slightly different, but usually acceptable if the recording is made by a party to the conversation (as in with a tape recorder concealed in the pocket.) A recording made legally is admissible as evidence if the rules of evidence are satisfied. For a case in which recorded phone conversations were essential to an excellent result in a child custody case, see the Idaho Supreme Court case cited on my profile page.
Best wishes for a favorable result, and please remember to designate a best answer.
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I dont know the value of someone promising or not promising a dog. Do not record a telephone call and do not leave a recorder set with voice activation somewhere hidden in a house or car all the time.
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In NYS one party to a conversation must consent to the recording. In other words, you can record your own telephone conversations but no those of third parties in which you are not involved.