http://www.discoverthenetworks.org/individualProfile.asp?indid=2169
"In 1980 Ayers and Dohrn surrendered to law-enforcement authorities, but all charges against them were later dropped due to an "improper surveillance" technicality -- government authorities had failed to get a warrant for some of their surveillance. Ayers' comment on his life, as reported by Peter Collier and David Horowitz in their authoritative chapter on Weatherman in Destructive Generation, was this: "Guilty as sin, free as a bird, America is a great country.""
Here is another reference:
"I do take issue with the statement in your news article that the Weathermen indictment was dismissed because of "prosecutorial misconduct." It was dismissed because of illegal activities, including wiretaps, break-ins and mail interceptions, initiated by John N. Mitchell, attorney general at that time, and W. Mark Felt, an F.B.I. assistant director.
William C. Ibershof, Mill Valley, Calif., Oct. 8, 2008