In January as Sen. Scott Brown (R-Mass.) negotiated with his Democratic opponent Elizabeth Warren over the details of a “People’s Pledge” to keep outside spending out of the Massachusetts senate race he stated:

“Attack ads from unaccountable outside groups that spend millions of dollars from anonymous donors portraying their opposition unfairly and misleading voters are wrong” — letter to Elizabeth Warren re: People’s Pledge.

Which Senator is standing in the way of better campaign finance transparency? The Sunlight Foundation is investigating who is holding up a bill to mandate electronic campaign finance filings. They've identified five Senators who won't say whether they put a hold on the bill, or whether they object to it: these five need to come clean.