With tax evasion the "victim" is the federal government...not the individual.

With respect to the individual victim, he has recourse to various procedures to discover the hidden assets of the defendant. It takes the form of a post trial deposition. However, if the defendant has already dissapated the funds, there really is very little to discover.

The most powerful tool in restoring the victim's funds is the desire of the criminal defendant to avoid a long prison term combined with the court's order of restitution. If the defendant still has the funds, he is more likely to react to the restitution order than the victim's attempts to discover hidden assets.

I have seen first hand how the federal government investigates criminal defendants. The FBI very often joins with the CID of the Internal Revenue Service to both determine probable cause to proceed, and then to locate the hidden assets of the potential defendant. The proceeds of a criminal enterprise are still subject to taxation even though illegally gained.Generally they will try to determine who, if anybody, is the number two man in the criminal enterprise, and force him to turn against the defendant in return for leniency. It works very effectively.