In 2012, what portion of non-citizens in the U.S. were registered to vote in violation of laws that prohibit non-citizens from voting in U.S. elections?

What do you think?  One percent, five percent, maybe 10%.  Maybe enough for election integrity laws?

The correct answer is a whopping 20%?

Laws in all 50 states generally forbid non-citizens from registering to vote in federal elections, but enforcement mechanisms are limited, and the vast bulk of illegal immigrants have fake IDs that can be used to register. Thus, a 2012 Harvard/YouGov survey revealed that 14% of non-citizens stated they were registered to vote, and 9% stated they “definitely voted” in the 2012 U.S. presidential election. In addition, database matches with consumer and voting records showed that 22% of non-citizens in the database were registered to vote, and 12% voted in the 2012 U.S. presidential election. The margin of sampling error for these results is plus-or-minus 4 percentage points with at least 95% confidence. Other surveys conducted in 2008, 2010, and 2013 found similar voter registration and voting levels among non-citizens. So-called “fact-checkers” have tried to dismiss these facts by quoting the opinions of selected “experts,” which are debunked at the 2nd and 3rd links below.