No; absolutely not.
An unrelated person can only claim a child (or any other unrelated person) that lived with him ALL year. Even then, the child may qualify as a
dependent, but because he is not related, he cannot be a qualifying child for
the earned income credit, child tax credit or Head of Household filing status.
Furthermore it is not the non-custodial parent's choice. The custodial parent (the
IRS goes by physical custody, not legal custody) has
first priority on claiming the children on her/his taxes; regardless of the amount
of support provided by the non-custodial parent. The non-custodial parent can
only claim the child as a dependent if the custodial parent gives permission
(on IRS form 8332) or if it's spelled out in a pre 2009 divorce decree.
Even if a divorce decree, dated after 2008, gives the non-custodial parent the
right to claim the child, he must still get form 8332 from the custodial
parent. A properly worded decree should require her to provide that form. https://www.irs.gov/pub/irs-pdf/f8332.pdf
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You should be aware of one other thing, for those years when the non-custodial parent is able to claim the child.
There is a
special rule in the case of divorced & separated (including never married) parents.
When the non-custodial parent is claiming the child as a
dependent/exemption/child tax credit; the custodial parent is still allowed to
claim the same child for Earned Income Credit, Head of Household filing status,
and day care credit. This "splitting of the child" is not available
to parents who lived together at any time during the last 6 months of the year;
then only one of you can claim the child for any tax reasons. The tax benefits
may not be split in any other manner.
Note in particular
that the non-custodial parent can never claim the Earned Income Credit, Head of
Household filing status or the day care credit, based on that child, even when the custodial parent has released
the exemption to him.
So, it's good idea to let the other parent know that you
will be claiming those items, as many first time divorced parents are not aware
of this rule and may try to claim those items, which will cause the IRS to send
out letters.
Ref: https://www.irs.gov/publications/p17#en_US_2017_publink1000170897
Scroll down to "Children of divorced or
separated parents (or parents who live apart)"
You can if you are the custodial parent.
