Police perjury, sometimes euphemistically called "testilying", is the act of a police officer knowingly giving false testimony. It is typically used in a criminal trial to "make the case" against defendants believed by the police to be guilty when irregularities during the suspects' arrest or search threaten to result in their acquittal. It also can be extended to encompass substantive misstatements of fact to convict those whom the police believe to be guilty, procedural misstatements to "justify" a search and seizure, or even the inclusion of statements to frame an innocent citizen. More generically, it has been said to be "[l]ying under oath, especially by a police officer, to help get a conviction."
In jurisprudence, prosecutorial misconduct or prosecutorial overreach is "an illegal act or failing to act, on the part of a prosecutor, especially an attempt to sway the jury to wrongly convict a defendant or to impose a harsher than appropriate punishment." It is similar to selective prosecution. Prosecutors are bound by a sets of rules which outline fair and dispassionate conduct.
A prosecutor is a legal representative of the prosecution in states with either the adversarial system, which is adopted in common law, or inquisitorial system, which is adopted in civil law. The prosecution is the legal party responsible for presenting the case in a criminal trial against the defendant, an individual accused of breaking the law. Typically, the prosecutor represents the state or the government in the case brought against the accused person.
Discovery, in the law of common law jurisdictions, is a phase of pretrial procedure in a lawsuit in which each party, through the law of civil procedure, can obtain evidence from other parties by means of methods of discovery such as interrogatories, requests for production of documents, requests for admissions and depositions. Discovery can be obtained from nonparties using subpoenas. When a discovery request is objected to, the requesting party may seek the assistance of the court by filing a motion to compel discovery. Conversely, a party or nonparty resisting discovery can seek the assistance of the court by filing a motion for a protective order.
In the legal system of the United States, a Brady disclosure consists of exculpatory or impeaching information and evidence that is material to the guilt or innocence or to the punishment of a defendant. The term comes from the 1963 U.S. Supreme Court case Brady v. Maryland, in which the Supreme Court ruled that suppression by the prosecution of evidence favorable to a defendant who has requested it violates due process.
Exculpatory evidence is evidence favorable to the defendant in a criminal trial that exonerates or tends to exonerate the defendant of guilt. It is the opposite of inculpatory evidence, which tends to present guilt.
Actual innocence is a special standard of review in legal cases to prove that a charged defendant did not commit the crimes that they were accused of, which is often applied by appellate courts to prevent a miscarriage of justice.
In the United States, the Jencks Act requires the prosecutor to produce a verbatim statement or report made by a government witness or prospective government witness, but only after the witness has testified.
Jencks v. United States, 353 U.S. 657 (1957), is a decision of the U.S. Supreme Court in which the court held that the federal government must produce documents relied upon by government witnesses in federal criminal proceedings.
Kyles v. Whitley, 514 U.S. 419 (1995), is a United States Supreme Court case that held that a prosecutor has an affirmative duty to disclose evidence favorable to a defendant pursuant to Brady v. Maryland and United States v. Bagley.
In United States criminal procedure, the Federal government and certain states have reciprocal discovery laws that compel defendants to disclose some information to prosecutors before trial. Within the federal court system, this material is referred to as reverse Jencks Act material, after the United States Supreme Court case which established the principle, Jencks v. United States.
Giglio v. United States, 405 U.S. 150 (1972), is a United States Supreme Court case in which the Court held that the prosecution's failure to inform the jury that a witness had been promised not to be prosecuted in exchange for his testimony was a failure to fulfill the duty to present all material evidence to the jury, and constituted a violation of due process, requiring a new trial. This is the case even if the failure to disclose was a matter of negligence and not intent. The case extended the Court's holding in Brady v. Maryland, requiring such agreements to be disclosed to defense counsel. As a result of this case, the term Giglio material is sometimes used to refer to any information pertaining to deals that witnesses in a criminal case may have entered into with the government.
Vincent Alfred Simmons is an American man who was a life prisoner at Angola State Prison in Louisiana, where he was sentenced to 100 years in July 1977 after being convicted of the "attempted aggravated rapes" of 14-year-old twin sisters Karen and Sharon Sanders of Marksville. Simmons has maintained his innocence throughout. By 1999 Simmons had filed numerous habeas corpus writs, but had not gained an evidentiary hearing by a Louisiana court. After receiving a copy of his evidence file in 1993, he had found that it contained exculpatory evidence that was not given to his court-appointed attorney by the District Attorney, and that there were inconsistencies in reports and statements of victims and witnesses.
The United States Constitution contains several provisions regarding the law of criminal procedure.
Washington v. Texas, 388 U.S. 14 (1967), is a United States Supreme Court case in which the Court decided that the Compulsory Process Clause of the Sixth Amendment to the Constitution is applicable in state courts as well as federal courts. Jackie Washington had attempted to call his co-defendant as a witness, but was blocked by Texas courts because state law prevented co-defendants from testifying for each other, under the theory that they would be likely to lie for each other on the stand.
Napue v. Illinois, 360 U.S. 264 (1959), was a United States Supreme Court case in which the Court held that the knowing use of false testimony by a prosecutor in a criminal case violates the Due Process Clause of the Fourteenth Amendment to the United States Constitution, even if the testimony affects only the credibility of the witness and does not directly relate to the innocence or guilt of the defendant.
United States v. Bagley, 473 U.S. 667 (1985), was a Supreme Court of the United States case that established the standard for materiality under Brady v. Maryland.
United States v. Ruiz, 536 U.S. 622 (2002), was a decision by the United States Supreme Court in which the Court held that Brady v. Maryland did not require prosecutors to disclose impeachment evidence during plea bargaining.
Smith v. Cain, 565 U.S. 73, 132 S. Ct. 627 (2012), is a United States Supreme Court decision clarifying the Brady v. Maryland standard for criminal discovery. Joshua Dressler has called Smith v. Cain the "most recent pronouncement on the discovery issue."
United States v. Agurs, 427 U.S. 97 (1976), was a case heard by the Supreme Court of the United States in 1976. The case clarified the obligation of a prosecutor to provide exculpatory evidence to a criminal defendant.
