It is part of our Constitutional guarantee of a fair trial. When the U.S. was a British colony, Americans saw for themselves how unjust it was to have regular people with no legal training go up against the British prosecutors. They decided we wouldn't do that here, and so the Constitution has a couple of references to fair trials. In time, U.S. courts decided that the trial could NOT be fair unless a defendant, no matter how poor, had someone with legal experience speaking up for them in court. So now, we have the public defender system. The U.S. Supreme Court case about this is GIDEON v. WAINWRIGHT: http://en.wikipedia.org/wiki/Gideon_v._Wainwright and if you're interested, there's a book your public library can easily get for you about the case, titled GIDEON'S TRUMPET by Anthony Lewis. The right to an attorney is being eroded by jurisdictions that want to charge the poor anyway: http://www.findarticles.com/p/articles/mi_m1295/is_n1_v61/ai_18980771 but I expect that, if this is ever taken up before the U.S. Supreme Court, these jurisdictions will have to knock it off. Depending on where you live, the public defenders may be well-financed and good at their jobs, or may receive amazingly low rates of pay compared to the prosecutors and be really awful at their jobs. Here is an excerpt from an article about death penalty cases that explains how poorly public defenders may be paid, in comparison to the salaries of prosecutors: http://www.prospect.org/web/page.ww?section=root&name=ViewPrint&articleId=7882 BEGIN QUOTE ---Unfortunately, few if any of the defendants on death row are provided with lawyers possessing the requisite skills and resources. Instead, poorly trained and underfunded court-appointed lawyers who provide abysmal legal assistance typically represent those death-sentenced prisoners. Tales of the pathetic lawyering provided by appointed counsel to their capitally charged clients are legion. Perhaps the most famous example is that of Calvin Burdine, whose court-appointed lawyer slept through significant portions of his trial. Another example is the case of Vinson Washington, whose court-appointed lawyer suggested to the defense psychiatrist that Vinson “epitomized the banality of evil.” Death-sentenced defendants are so frequently provided with poor representation that, in 2001, Supreme Court Justice Ruth Bader Ginsburg commented that she had never seen a death-penalty defendant come before the Supreme Court in search of an eve-of-execution stay “in which the defendant was well-represented at trial.” One reason that appointed counsel perform so poorly is that they are grossly undercompensated. In some cases, capital-defense attorneys have been paid as little as $5 an hour. Not surprisingly, these paltry rates of compensation have yielded an equally paltry quality of representation. As was succinctly noted by the 5th U.S. Circuit Court of Appeals in its review of the quality of representation provided by a court-appointed lawyer to a capitally charged defendant in Texas: “The state paid defense counsel $11.84 per hour. Unfortunately, the justice system got only what it paid for.” --- END QUOTE