Originally Posted by vulcan

Just guessing here........ a signed tax return has personal details, if you're married or single, have dependents etc. That would count as supporting evidence to your N-400 answers along with other docs we may send in.

I doubt they're interested in your tax liability............just the basis for your return.

I guess they might figure no ones dumb enough to lie on their N-400 and on their last 3-5 years tax returns