Balko is batting them down. He debunks the notion that "the government can't punish you for a crime without first convicting you":
Under most civil asset forfeiture laws, the property itself is accused of the crime. The government then files a complaint against the property in civil court. Because it's a civil proceeding, the government's standard of proof is much lower. In fact, in some states the burden is on the property owner to prove he or she earned the property legally. That can be a difficult thing to prove.
The cost of fighting a seizure in court can often exceed the value of the property itself. As of 2008, the federal asset forfeiture fund had over $3 billion in assets. Less than 20 percent of the people from whom that property was taken were ever charged with a crime.