If you are the custodial parent where the child physically lived for more than half the year then the other parent cannot claim the child at all without a signed 8332 form form you that release the dependent. Even with the 8332 only the custodial parent can claim the EIC and dependent care credits if those apply.
Once a child reached the age of emancipation (age 18 in most states) then ONLY the parent where the child physically lived can claim.
If a dependent that you are entitled to claim has already been claimed by another taxpayer, your e-filed return will reject since the child's SSN has already been used (either intentionally or in error such as a mistyped SSN).
Your only recourse is to file a correct tax return, claiming what you are entitled to claim, then print and mail the return.
The IRS will process both returns and pay any refunds. Shortly (within a year) the IRS will mail letters to both taxpayers asking if their tax return was filed in error and suggesting that they amend if they improperly claimed the child.
If neither taxpayer amends, the IRS will send a second letter asking for each taxpayers proof that they are entitled to claim the dependent, such as proof that the child physically lived with them more than half the year. School records, child care records, household receipts, medical bills, etc., that show that the child lives with you should be retained.
The IRS will evaluate each taxpayers claim and award the dependent to one taxpayer, the other will have to payback any refund received plus interest and possible penalties. The parent that had physical custody usually always wins.
Do not ignore the letters or you will loose.
**Disclaimer: This post is for discussion purposes only and is NOT tax advice. The author takes no responsibility for the accuracy of any information in this post.**
