A co-conspirator is a person that acts in conjunction with another person to defraud another party through the use of either legal or illegal means. If the end result is a crime that is occurring against one or more persons, then it does not matter if the way in which it was carried out was legal, such as through hiking electronics prices. Both the conspirator and co-conspirator will be charged in the same way for the act that was illegally committed.
A co-conspirator might be able to strike a plea bargain with the courts to give evidence regarding their partner or partners in the crime; this only applies if their role was not as damaging as that of the others whom they give evidence against.