Yes, but are you OK with property confiscation before a man is found guilty by a court of law?
If there are assets which may have been involved in the criminal activity itself -- a vehicle to transport, a warehouse to store, land to grow, a laboratory to manufacture -- or if there are assets gained by the illegal activity -- cash, paintings, houses, clothes -- I believe it is lawful to hold and freeze those assets until a verdict has been reached.
If that's whats meant by "confiscation" or "seizure", then yes. I don't believe that the government has the power to take possession and/or dispose of the assets until a guilty verdict has been reached.
Bear in mind that we imprison people "before they're found guilty by a court of law", so let's not get ourselves all worked up about a little temporary asset holding.