The Sixth Amendment guarantees criminal defendants the right to counsel, but that does not mean all defendants receive good representation. Too often, their defense is not even minimally adequate.

Public defenders are lawyers who work for the court system representing indigent defendants instead of maintaining their own practices. Some are passionate civil libertarians who choose to represent the destitute, damned, and despised. Some simply prefer a regular paycheck to the vicissitudes of private practice. Contrary to their reputation, many are great lawyers. But even great public defenders can find it difficult to do great work in every case.

Public defenders are often forced to take on caseloads heavier than any lawyer can competently or ethically handle. According to a 2005 report commissioned by the Missouri Bar, caseload, more than any other factor, determines which public defender offices do good work and which do not. No lawyer, no matter how skilled, can do a competent job on 200 felony cases a year. In some public defender offices, the caseload is more than twice that.

Overloaded defenders are forced to triage, exchanging quick pleas in some cases for the ability to fight in others. They have to decide which cases will benefit from extra attention and which will not. Cases are "pled out" without time to conduct a real investigation, interview witnesses, or even determine whether there are grounds to challenge the police version of the facts.

Some clients, of course, are just guilty. They are caught on videotape; they confessed; their crimes are established by DNA, fingerprints, or the testimony of a victim who can describe something unique about them. Their crimes are unsympathetic, so there's little hope for jury nullification. Those cases can and should be settled with a plea agreement that gives the defendant the best result that can be negotiated.

But it is not always easy to know which cases are the hopeless ones if all you do is read the offense report and spend a few minutes talking to the defendant and the prosecutor. Without putting in the time required to investigate the facts, the law, and the witnesses, it is unethical to recommend that a client accept a plea bargain. Maybe the offer represents the best possible result, but maybe the client is completely innocent and just too frightened to disagree.

Public defenders are often strapped for resources. Investigators, experts, computer animations, and laboratory tests cost money, sometimes a lot of money. Without such resources, innocent people can be convicted, something that happens more often than most of us want to believe. The work of the Innocence Project has led to the exoneration of hundreds of individuals based on DNA testing that was once considered too expensive or esoteric to perform in "routine" cases. An indigent defendant faces a Catch-22: Until a scientific test is performed and the results prove helpful, he cannot show he has a due process right to the funds necessary to perform the test.

Even in counties with public defender offices, many indigent defendants are represented by appointed private lawyers (usually because of a conflict of interest between defendants). Attorneys accepting court appointments often must maintain good relationships with the judges and court staff. This can mean bringing morning donuts, contributing to re-election campaigns, avoiding aggressive pre-trial motions that tie up the court, pleading out as many cases as possible, limiting requests for expensive investigators and experts, or trying not to bill too many hours in a given case. I've known lawyers who have been removed from the appointment list because they zealously represented their clients. I've known judges who have fired appointed counsel while a case was still awaiting trial because the lawyer was putting too many hours into the case.

A court sometimes will refuse to pay an appointed lawyer for hours it deems unnecessary. If the lawyer spends time researching legal theories that do not pan out, he may not be paid for that work. Sometimes the amount received is less than a good lawyer's overhead for the time spent on the case. No lawyer should be given a Hobson's choice between supporting his family and defending his client, but that is where appointed attorneys can find themselves if they work too hard.

For paying clients, a good criminal defense is expensive, from thousands of dollars for a misdemeanor to potentially millions for a serious felony. The difference between an appointed lawyer and a retained lawyer can be marginal, but sometimes cases are won or lost on such marginal differences. I would not expect the taxpayers to fund an O.J. Simpson–style litigation team for every defendant, and not every case would benefit from such extravagance.

I would, however, expect that before the taxpayers spend hundreds of thousands of dollars to incarcerate one of their neighbors for years, branding him virtually unemployable for life and making him part of America's permanent undercaste, they would want to ensure that he had a competent lawyer, with adequate resources and adequate time to do everything possible within the law to help his client. It is not an extravagance to make sure that before a man's life is destroyed or taken from him, his defense has fully tested every element of the government's case. The cost of an adequate defense pales against the cost of incarcerating an innocent man.

Clay S. Conrad (csconradesq@aol.com) is the author of Jury Nullification: The Evolution of a Doctrine (Carolina Academic Press). He is a shareholder in the Houston law firm Looney & Conrad, P.C., specializing in criminal defense and appellate litigation.