Not true - 已經免稅了就不能再減CTC, 0-??=0. 州稅不隨TREATY.

This is a commom pitfall, no where mentioned that you can not claim child tax credit if you do not pay tax, it is separate from your tax postion as long as you file 1040 (which means tax status as resident or resident allien).

Please look at the instructions of form 8812:additonal child tax credit carefully. http://www.irs.gov/instructions/index.html search form 8812

As mentioned, my friend confirmed it with local IRS office, and she got the credit for the past three years.