ACORN has put itself in a position of public trust by acting as an intermediary between individuals and the government: helping people register to vote, helping them get government funding, helping the government count citizens. Whether it supported pimping or not, it is clearly suggesting ways for people to defraud the government by cheating on taxes. This is criminal, and it would seem to provide an obvious reason for the government to discontinue all public funds to ACORN immediately.
I have read in several places (e.g., here) that it may be unconstitutional for Congress to cut off funding specifically for ACORN because it could count as a "bill of attainder." `This seems more than a little stretch of the concept to me. A bill of attainder "is an act of the legislature declaring a person or group of persons guilty of some crime and punishing them without benefit of a trial." The laws in question would say nothing about whether ACORN was engaged in criminal activity, nor would it apply any form of punishment, but merely cut off government funding. This could only be considered a form of punishment in some twisted socialist worldview. If Congress can grant funding to specific groups, how could it not be allowed to rescind funding for specific groups?
In addition to ACORN's overtly fraudulent activities, its covertly partisal political purpose is also coming to light. One of the arguments in ACORN's favour that I did not mention is yesterday's post is, "Why are the Republicans picking on a group that helps poor people?" But ACORN is not just a group that helps poor people; it is a group that helps poor people organize to support liberal politics. Of course, it is entirely within its right to do so, but not with federal funding.