Civil forfeiture. From wikipedia: http://en.wikipedia.org/wiki/Civil_forfeiture#United_States "In civil cases, the owner need not be judged guilty of any crime; it is possible for the Government to prevail by proving that someone other than the owner used the property to commit a crime. In contrast, criminal forfeiture is usually carried out in a sentence following a conviction and is a punitive act against the offender."

Or if you're up for a long read: http://www.newyorker.com/reporting/2013/08/12/130812fa_fact_...

How is that reasonable?

It's a regular occurrence that people who are probably innocent have property seized under forfeiture laws, and never get the property back. Some of them are never even charged. Others are charged but beat the charges.

It's worse, though. While it's possible to get the property back, you have to prove by a preponderance of the evidence that the property had no connection to a crime. That's a difficult thing to do.

It's not. But it's not like the US Justice system is not known for its acting grossly out of proportion.

Different standards of evidence, I guess. To be jailed for something, the standard of evidence is higher than to confiscate money gotten through that same thing.

It's not, but allowing it is easier for politicians than raising taxes to pay for all the policing that the voters want.