CONSPIRACIES

A Conspiracy is an agreement between two or more people to commit a particular crime. In the legal context if you make such an agreement, intending that it be carried out, then you and everyone you agreed with are guilty of the crime you agreed to carry out. 

Those involved in the alleged conspiracy can have particular roles. For example, in a drugs conspiracy you would have drugs runners, couriers, managers and others. To be guilty, you need to have agreed to have played some part in carrying out what was intended.