Is drawing on money legal

Answer 1

United States currency and coinage are governed by federal law through the U.S. Treasury Department. Generally, it is illegal to fraudulently deface, mutilate, impair, diminish, falsify, scales or lightens any coins minted or "coined" in the United States or any foreign coins which are by law made current or are in use or circulation as money within the U.S. (18 U.S.C. 331)

It is also a crime to fraudulently possess, pass, publish, sell or attempt to possess, pass, publish, sell or bring into the U.S. any such coin with knowledge that the coin has been altered, mutilated, defaced, etc. (18 U.S.C. 331)

What this means is:

If you destroy the bill while drawing on it, it's illegal.

If you alter it by means of drawing to fraudulently change it's value, (from $1 to $10, say), it's illegal

If you deface it to the point where it's not recognizable, it's illegal.

If you draw glasses, a mustache and a funny hat on Abe Lincoln, it's perfectly legal.