As far as the IRS is concerned, the custodial parent--the parent who has the child for the most nights of the year--is the parent who can claim the child as a dependent. That parent can claim the child-related credits such as earned income credit, childcare credit and the child tax credit. For 2017 and prior--you could also get the personal exemption for your child. The custodial parent is also the one who can file as Head of Household with that child as a dependent.
IF you signed a Form 8332, then the other parent--the non-custodial parent--could get the personal exemption for the child in 2017 and in prior years, and could claim the child tax credit. The non-custodial parent can never claim the child in order to get earned income credit or the childcare credit, nor could they file as Head of Household based on claiming that child. Those credits always go to the custodial parent--even in the "off" year that you cannot fully claim the child if you signed 8332.
For 2018 and beyond, there is no longer a personal exemption. It has been replaced by the $500 credit for a dependent.
https://ttlc.intuit.com/questions/4499708-what-is-the-500-credit-for-other-dependents-family-tax-cre...
Courts cannot violate the tax laws. You may need a better attorney who understands the tax laws regarding claiming your child as a dependent. If the other parent claims the child and files first, you will not be able to e-file. In that event, print, sign and mail your tax return. The IRS will sort out who can claim the child based on the tax laws.
**Disclaimer: Every effort has been made to offer the most correct information possible. The poster disclaims any legal responsibility for the accuracy of the information that is contained in this post.**
