The prosecutor has more control over life, liberty, and reputation than any other person in America. His discretion is tremendous. He can have citizens investigated and, if he is that kind of person, he can have this done to the tune of public statements and veiled or unveiled intimations. Or the prosecutor may choose a more subtle course and simply have a citizen’s friends interviewed. The prosecutor can order arrests, present cases to the grand jury in secret session, and on the basis of his one-sided presentation of the facts, can cause the citizen to be indicted and held for trial. He may dismiss the case before trial, in which case the defense never has a chance to be heard. Or he may go on with a public trial. If he obtains a conviction, the prosecutor can still make recommendations as to sentence, as to whether the prisoner should get probation or a suspended sentence, and after he is put away, as to whether he is a fit subject for parole. While the prosecutor at his best is one of the most beneficent forces in our society, when he acts from malice or other base motives, he is one of the worst.
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There is a most important reason why the prosecutor should have, as nearly as possible, a detached and impartial view of all groups in his community. Law enforcement is not automatic. It isn’t blind. One of the greatest difficulties of the position of prosecutor is that he must pick his cases, because no prosecutor can even investigate all of the cases in which he receives complaints. If the Department of Justice were to make even a pretense of reaching every probable violation of federal law, ten times its present staff would be inadequate. We know that no local police force can strictly enforce the traffic laws, or it would arrest half the driving population on any given morning. What every prosecutor is practically required to do is to select the cases for prosecution and to select those in which the offense is the most flagrant, the public harm the greatest, and the proof the most certain.
If the prosecutor is obliged to choose his cases, it follows that he can choose his defendants. Therein is the most dangerous power of the prosecutor: that he will pick people that he thinks he should get, rather than pick cases that need to be prosecuted. With the law books filled with a great assortment of crimes, a prosecutor stands a fair chance of finding at least a technical violation of some act on the part of almost anyone. In such a case, it is not a question of discovering the commission of a crime and then looking for the man who has committed it, it is a question of picking the man and then searching the law books, or putting investigators to work, to pin some offense on him. It is in this realm—in which the prosecutor picks some person whom he dislikes or desires to embarrass, or selects some group of unpopular persons and then looks for an offense, that the greatest danger of abuse of prosecuting power lies. It is here that law enforcement becomes personal, and the real crime becomes that of being unpopular with the predominant or governing group, being attached to the wrong political views, or being personally obnoxious to or in the way of the prosecutor himself.