^^^ A recording of the man saying it to her was played so maybe people having the ability to record anything and anyone who is around them is what we all should be getting used to.
A couple things......
In many states the recording would be inadmissible as evidence of anything. Massachusetts, for example, requires consent to record audio or video of another person.
Secondly, this is just further proof in my mind why personal electronic devices other than calculators should be banned from all schools.