Suppose we have an illegal exchange which takes place- is there a rule of thumb for who is at fault, the buyer or the seller?
For example, I have three situations.
1- A buyer purchases illegal drugs off of an unlicensed dealer, both are aware of the illegality of the purchase
2- A buyer purchases a car at what they believe to be a legitimate used-car dealer, however the car is actually stolen. The dealer is aware the car is stolen.
3- A hospital purchases an expensive software system from a company to serve some purpose. The software fails to comply with some governmental regulation which would be non-obvious to either the software producer nor the hospital.