First of all, I agree with RefDaddy that you were a little quick on the trigger with the T. However, I wasn't there and you were, so maybe taken in context, that remark warranted the call.
If after making the call, you get a statement from a player like that, you should check with your partner to see if he (OK, he
or she, Juulie) heard it also. If your partner says the kid was correct, just wave it off and explain to the scorer that you misheard the kid and your partner verified it.
If your partner either didn't hear anything, or heard what you heard and you are positive you heard it that way, stick with your call.
Then tell the kid you'll give him another T for lying.