A common argument in favor of any new proposed law is that if someone opposes the law then the person who opposes the law is in favor of whatever the law is supposed to prevent. For instance, whenever someone suggest that laws against drugs be repealed then the argument is then made that anyone who makes that argument is therefore in favor of drug use. Or when someone suggests that prostitution be legal the argument is made that anyone who makes that argument is a proponent of prostitution.
Also when a new government program is proposed, if someone dares suggest that the government has no business providing a good or service then whoever dares make that suggestion doesn't want that service provided at all. For instance, anyone who dares suggest that the government has no role in providing health care is accused of wanting people to not be able to access health care.
These are two variations of the same fallacy. It is assumed that if the government isn't involved then the issue is unresolved, and anyone who opposes a government solution then opposes a solution at all.
It's a very nasty fallacy, as it often puts those who oppose government solutions on the defensive. They have to defend themselves against many spurious vice charges, such as indulgence in prostitution or drugs, or the vice of greed since they allegedly want to keep their money rather than solve some problem that the government would use that money to solve. Loaded questions such as whether anybody who opposes welfare ever gives to charity are thrown up to distract from the main argument of the program itself.
As any proponent of liberty knows, it is quite possible to oppose something and oppose laws against it at the same time, such as opposing racism and opposing thought crime laws. It is also possible to support something and oppose laws mandating it at the same tme, such as charity. The simple solution when faced with the statist fallacy is to call it for what it is. A more argumentative solution is to say "so you require a law for you to do what is right?"