@DalhousieLucy wrote:
Ideally, the non custodial patient is supposed to only be able to claim the tax credit if the custodial parent signs 8223 but that is not what happens in practice. I have not signed and the non custodial parent claims our child every year. His tax accountant wrote in the form “custodial parent refused to sign” and has successfully filed annually since 2015
If you don't claim the child, the IRS won't have anything to investigate, they don't know where the child lives and don't know the claim is wrong unless you tell them. But if you do also claim your child as a dependent, the IRS should investigate--per regulations, they are not allowed to accept any other written excuse for custody orders signed after 2008. The IRS should send a notice CP87A to both taxpayers who claimed the child.
https://www.irs.gov/individuals/understanding-your-cp87a-notice
If both parents continue to claim the child, the IRS will send a CP75 notice asking you to provide proof. https://www.irs.gov/individuals/understanding-your-cp75-notice
I can't speak to whether or not the IRS enforces the regulations in the same in every case--they should do so. And the regulations say the dependent goes to the custodial parent.
However, as mentioned, if the custodial parent is ordered to allow the non-custodial parent to claim the child and they refuse or interfere in some way, the non-custodial parent can complain to the family court.
