Deductions & credits

Question in regards.

 

Based on what I read here.  If the children involved in a divorce no matter what was decided at the local/county level live with you more then 50% of the nights in a year you are able to claim them as dependent who qualifies for the tax benefit/reductions.  Unless there is a 8332 giving up your right to claim them for benefit/reduction purpose on your taxes regardless of how many nights that child spent at your residence.   Is this form needed if you claim the child every year and that child lives with you for more then 50% of the nights?  And this form is only needed if the parent claiming the child resides where the child being claimed did NOT spend more then 50% of the nights?