Excellent article on prosecutorial discretion and over-criminalization in the Columbia Law Review by Glenn Reynolds, a law professor at the University of Tennessee. Its worth quoting at length on the lack of meaningful limits on charging discretion, and the pressure to plead that over-charging creates:
“Despite the problems described above, most of us remain safe. Prosecutors have limited resource and there are political constraints on egregious overreaching. And presumably, most of the time prosecutors can be expected to exercise their discretion soundly. Unfortunately, these limitations on prosecutorial power are likely to be least effective where prosecutors act inappropriately because of politics or prejudice. Limited resources or not, a prosecutor who is anxious to go after a political enemy will always find sufficient staff to bring charges, and political constraints are least effective where a prosecutor is playing to public passions or hysteria.
Once charged with a crime, defendants are in a tough position. First, they must bear the costs of a defense, assuming they are not indigent. Second, even if they consider themselves entirely innocent, they will face strong pressure to accept a plea bargain—pressure made worse by the modern tendency of prosecutors to overcharge with extensive “kitchen-sink” indictments: Prosecutors count on the fact that when a defendant faces a hundred felony charges, the prospect that a jury might go along with even one of them will be enough to make a plea deal look attractive. Then, of course, there are the reputational damages involved, which may be of greatest importance precisely in cases where political motivations might be in play. Worse, prosecutors have no countervailing incentives not to overcharge. A defendant who makes the wrong choice will wind up in jail; a prosecutor who charges improperly will suffer little, if any, adverse consequence beyond a poor win/loss record. Prosecutors are even absolutely immune from lawsuits over misconduct in their prosecutorial capacity.”