Concerning Categorical Legislative Prohibitions of Defenses in Criminal Cases

NACDL opposes categorical, legislative prohibition of specific defenses.


With this resolution, NACDL seeks to address legislative efforts to categorically prohibit certain defenses. It is NACDL’s position that such laws undermine foundational principles of our criminal justice system and unnecessarily supplant well-established rules of evidence that balance principles of relevance and due process rights of accused persons.

The right to due process, enshrined in the Sixth and Fourteenth amendments to the United States Constitution and analogous state constitution provisions throughout the United States, includes the rights to confront, cross examine and compel the attendance of witnesses. Considered together, all of these rights are integral to ensuring the singular fundamental right of criminally accused persons to present a defense.  

The right to present a defense encompasses the presentation of any evidence that shows that an accused person either did not commit the crime or that his or her actions were excused, justified, or mitigated in some way. Where the law allows an affirmative defense, mitigation or justification, it reflects society’s collective determination, enshrined in the law, that conduct that may otherwise be considered worthy of punishment may be excused or considered less blameworthy. Some defenses like defense of self or others, necessity, and duress are such fundamental precepts that they are universally understood to afford context and justification for otherwise unlawful conduct. Other defenses and forms of mitigation reflect enormous advances in our understanding of human psychology and brain development. And regardless of why a criminal or violent act may have been committed, proof of guilt beyond a reasonable doubt is always required.

It is in the crucible of trial that these general principles are applied to facts through the presentation of testimony and evidence to juries of our peers. That process is guided by accepted rules of evidence and established case law interpreting the application of those rules and defining the defenses that have developed through common law and are protected by state and federal constitutions and statutes.

Outside of the courtroom, the tragic circumstances of many cases justifiably give rise to a public outcry. Sympathy for victims of crime targeted because they are vulnerable, oppressed, or marginalized often leads to important and meaningful community advocacy to legislate policy changes that protect and make life safer for members of these groups. The impulse to legislate solutions in the wake of tragic cases, however, has led lawmakers to pass statutes designed to categorically prohibit certain defenses and thereby undermine the ability of defendants to present a defense. These prohibitions derive from the public discourse around high profile cases which tends to stir passions and to distill complicated facts and circumstances into sensationalistic headlines and rhetorical soundbites.  

Categorically prohibiting defenses through legislation may feel like a meaningful solution in the aftermath of a high-profile crime, but it is a misguided impulse. These laws dramatically impinge on accused persons’ rights to confront their accusers and mount a defense. Evidence at trial, whether presented by the prosecution or the defense, must be adapted, limited, and shaped to comport with constitutional requirements of due process and to fulfill the practical purpose of trial, the pursuit of truth. Because categorical prohibitions of defenses do not evolve through well-considered case law, they must be mechanically applied by judges without regard to the trial’s truth-seeking function. Predictably, limiting the constitutional right of accused persons to mount a defense results in coerced guilty pleas, false convictions and convictions of more serious crimes than legally justified by the circumstances.

Statutes that limit defenses or the evidence that juries are permitted to consider also undermine the trust that the public has and should have in the ability of juries to reach just verdicts. Legislation that focuses on limiting certain defenses and the consequential media attention that follows encourages the public, to believe, incorrectly, that trials are conducted by judges mechanically applying the law instead of through an adversarial process culminating in a fair jury verdict that is based on a thorough and searching consideration of all of the relevant evidence at trial.  

NACDL seeks to promote transparent trial processes and to educate the public that trials must be a search for truth through the complete and rigorous examination of all relevant evidence and consideration of any argument for acquittal or mitigation presented by the unique facts and circumstances in each case and opposes categorical, legislative prohibition of specific defenses.


NACDL opposes categorical, legislative prohibition of specific defenses:  

Whereas, criminal trials are governed by well-established evidentiary rules that balance the admission of relevant evidence that is not unfairly prejudicial with the constitutional requirements that protect all peoples’ right to mount a defense; and

Whereas, defenses to criminal charges are not raised by mere articulation of a legal theory such as self-defense or necessity, but rather through the presentation and rigorous examination of the unique facts and circumstances of each case; and

Whereas, the availability of a defense may only be determined through a fair and full trial at which all relevant evidence has been presented, including evidence of behavior and views that may be socially unacceptable and offensive to many; and

Whereas, the categorical, legislative prohibition of specific defenses can have the effect of unintentionally limiting the ability of accused persons who themselves are members of marginalized groups from putting forward a legitimate defense that references or contextualizes their membership in that group; and

Whereas, the categorical, legislative prohibition of specific defenses falsely assumes that judges are not capable of determining what is relevant and admissible evidence and that jurors will not follow instructions and are incapable of rendering fair and unbiased verdicts; and

Whereas, implicit biases and prejudice operate in an insidious manner when not explicitly addressed and challenged in the adversarial process; and

Whereas, categorical, legislative prohibition of specific defenses increases the risk that these implicit biases will not be openly addressed and directly confronted during the course of the trial; therefore  

Be it resolved that the categorical, legislative prohibition of criminal defenses undermines the constitutional right to present a defense; and

Be it further resolved that judges presiding over individual case are in the best position to apply long-established rules of evidence to the unique facts and circumstances of the cases which come before them; and

Be it further resolved that properly instructed jurors are presumed to follow the instructions given to them by judges, to weigh the facts before them, consistent with their duty to resolve cases without bias and prejudice; and

Be it further resolved that the full and transparent exposure and examination of bias and prejudice in an open courtroom guided by the principles of due process and the right to confront witnesses is the best method of de-stigmatizing societally marginalized individuals who come into the criminal justice system whether as witnesses, victims or defendants; and  

Be it further resolved that because NACDL envisions a society where all individuals receive fair, rational, and humane treatment within the criminal justice system, it opposes the enactment of categorical legislative prohibitions of specific defenses that undermine the foundational principles of our criminal justice system and are neither fair, rational nor humane; and  

Be it further resolved that the constitutional right of accused persons to present a defense is best assured by assiduous application of existing rules of evidence and principles of relevance and materiality, judicial determination of the availability of legal defenses after a full and fair presentation of all relevant evidence, and thoughtful deliberation by properly instructed jurors. NACDL therefore opposes the categorical, legislative prohibition of specific defenses, because they undermine all of these processes.  

Resolution of the Board of Directors
February 16, 2019

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