Conspiracy
The word conspiracy comes from the Latin "con spire", which means "to breathe together". A conspiracy is a group of people who have an agreement to engage in illegal conduct. It is increasingly common for unscrupulous, political motivated prosecutors to misuse the concept of conspiracy to charge an innocent person of conduct which he never engaged in, but someone else may have.
In the United States, most criminal laws regarding conspiracy require that an overt act in furtherance of the conspiracy be committed before a crime is said to have occurred. This overt act in and of itself need not be illegal. For example, if two or more persons plot to rob a bank, and one of these commits an overt act in furtherance of the plot, such as obtaining the schedule of security guards at the bank, or blueprints of the bank, the plotters may be charged and convicted of conspiracy to rob a bank.