The offender (and his brother) will have to challenge the criminal/civil forfeiture of the home. Extensive evidence regarding no ill-gotten (drug) funds used to pay for the home will be necessary. Of course, a qualified attorney is required.
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I assume from your question that the government has already filed a notice of forfeiture, meaning that it intends to take ownership of the home from the offender. (If no notice of forfeiture has been filed, then this is a totally different situation.) As another lawyer already said, both the offender and the brother can, and should, challenge the forfeiture. The brother should retain his own lawyer to represent him in this process; the lawyer representing the offender cannot represent the brother in fighting the forfeiture.
Under federal forfeiture law, a person with an ownership interest can challenge a forfeiture by demonstrating that he is an "innocent owner." That requires the brother to prove two things: (1) that he is one of the owners, and (2) that he did not know and had no reason to know that the house was being used to manufacture meth. It appears that one substantial hurdle here is proving that the brother is one of the owners. That could depend on how the inheritance was structured, when the offender took possession, and how long the meth lab has been in operation. That's just one reason why the brother needs a qualified attorney to represent him in this process.
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