It is harder than may appear at first sight for a state to create a set of laws that enables the state to confiscate assets of criminals. Any law enabling confiscation must be just and must only enable confiscation of proceeds of crime which cannot be returned to the victims of crime. In England and Wales the Proceeds of Crime Act enables confiscation where a person is convicted of a serious offence and has a criminal lifestyle. Under English law having a criminal lifestyle does not mean behaving like a criminal but is defined in Section 75 of the Proceeds of Crime Act
75Criminal lifestyle(1)A defendant has a criminal lifestyle if (and only if) the following condition is satisfied. (2)The condition is that the offence (or any of the offences) concerned satisfies any of these tests— (a)it is specified in Schedule 2; (b)it constitutes conduct forming part of a course of criminal activity; (c)it is an offence committed over a period of at least six months and the defendant has benefited from the conduct which constitutes the offence. (3)Conduct forms part of a course of criminal activity if the defendant has benefited from the conduct and— (a)in the proceedings in which he was convicted he was convicted of three or more other offences, each of three or more of them constituting conduct from which he has benefited, or (b)in the period of six years ending with the day when those proceedings were started (or, if there is more than one such day, the earliest day) he was convicted on at least two separate occasions of an offence constituting conduct from which he has benefited. (4)But an offence does not satisfy the test in subsection (2)(b) or (c) unless the defendant obtains relevant benefit of not less than £5000. The test is not really defined in a way that most ordinary people would understand as a criminal lifestyle: the offence must be serious, carried on over a six month or more period and there has to be an element of repetition.
In the United States there are many rules enabling confiscation of the assets of a criminal but Civil Asset Forfeiture enables police to seize goods of suspected criminals that is to say those who have not been convicted and are presumed innocent. Under this program (as the Americans call it) cash and goods to the value of $4.3 billion was seized in 2012; the local police get a cut of the seizures, which itself must be wrong in principle.
It can lead to unjust results: confiscating a house because the police saw a family member (not the owner of the house) dealing drugs on the porch. It also seems more aimed at the small time offender rather than the big cartel type criminals.
It strikes me that lawmakers are reactive when it comes to criminal confiscations and rather than going to the trouble of figuring out principles that should apply and drafting the laws accordingly, they are going for the easy option of making rules without regard to principles and that is always dangerous and oppressive.