Overcharging, in law, refers to a prosecutorial practice that involves "tacking on" additional charges that the prosecutor knows he cannot prove.^[1] It is used to put the prosecutor in a better plea bargaining position.^[2] The term has been defined in different ways. Alschuler writes that "to prosecutors, overcharging is accusing the defendant of a crime of which he is clearly innocent to induce a plea to the 'proper' crime. Defense counsel identify two types of overcharging. 'Horizontal' overcharging is the unreasonable multiplying of accusations against a single defendant. He may be either charged with a separate offense for every technical criminal transaction in which he participated, or the prosecutor may fragment a single criminal transaction into numerous component offenses. 'Vertical' overcharging is charging a single offense at a higher level than the circumstances of the case seem to warrant."^[3] Vertical overcharging is deemed to be the more abusive of the two practices.^[4] In defense of overcharging, it has been argued that in order to obtain a plea bargain that results in a lower sentence than the prosecutor's original position, while still obtaining a penalty that promotes public safety, the prosecutor must select an initial charge higher than is penologically appropriate.^[5]

Although theoretically overcharging is impermissible, courts are reluctant to dismiss charges that are supported by probable cause.^{[citation needed]} American Bar Association guidelines discourage overcharging, but do not prohibit it.^[6] It has been said that rules aimed at combating prosecutorial vindictiveness that force prosecutors to justify any distinct indictments brought subsequent to an initial charge raise the possibility of overcharging.^[7] It has been argued that restrictions on the current practice of plea bargaining would most likely result in a reduction in overcharging by the prosecutor.^[8]