You didn't state the exact age of your child or what state you are in, but ...
In most states, a child is "emancipated" at age 18. But that can vary by state, so you need to check the age in your state.
If the child was "emancipated" for over 6 months during the year, the non-custodial parent can NOT claim the child as a dependent. Court orders can not change that. If the non-custodial parent were to claim that child as a dependent, that would be tax fraud.
