Taking Deduction for Adult Child Outside of Divorce Decree?

[Tim-in-Houston]

Divorced 10+ years.  Have 2 adult children (22 & 19 years old) both away in college.  I provide ~90% of their total financial support, yet my divorce decree grants each parent be allowed to claim a tax deduction for one child.  Former spouse will not sign paperwork to give me the deductions for both kids, despite the fact I clearly provide the majority of the financial support for both children.  My house is their residence when they are home from college too.

Do I have any options whereby I can claim both kids on my tax return?  Seems unfair one parent can claim a tax deduction for an adult child, when in reality they provide almost no financial support to the child they are claiming on the tax return.   Note:  there is no spousal support being paid, and child support is no longer owed.  Or, is it shame on me for not realizing this situation continued past the kids' high school graduation?

[AmyT]

You do have the option to claim both of your children on a paper-filed return and let the IRS make the determination.

The IRS will eventually contact both of you to figure out who gets to claim the dependent. The losing party will then be liable for any additional taxes, penalties, and/or interest as a result of the false claim.  Because the IRS will need to make a determination as to who can legitimately claim the child as a dependent (after they have contacted both of you and have received a response from both of you), this process can take a considerable amount of time.  

[Tim-in-Houston]

Thanks Amy. To clarify:

Did my former spouse actually make a "false claim"?  The divorce decree stipulates she can claim 1 child on her tax return.

My contention is that my former spouse is not providing the majority of the support (not even close) for that child for the 2016 tax year.   Does the divorce decree trump the fact I provide the majority of the support?

[AmyT]

Generally, from the IRS's perspective, the person who provides the majority of support for the child (and has custody, if appropriate) gets to claim the child regardless of what the divorce decree states.  I'm not sure that, since she was following, the divorce decree, she has made a false claim, but since you provide the majority of the children's support, there is certainly a very good argument that you are entitiled to claim both children as your dependents.