[quote]No, you cannot. [/quote]

Just went and reread your post, if you still paid child support after the date of filing and can prove that you paid it (a cashed check with child support written on the memo section is one way), then you should be able to deduct that. You won't be able to deduct what you paid prior to the filing date. And you will still be responsible for any difference.

One way to clear this up is to get your stbx to sign a statement (the signature will need to be notarized)stating the amount that you paid from the date of filing on.