What are the limits to &quot;cross examination?&quot; A witness takes the stand, and answers a number of questions about the issue in controversy. Then the opposing side gets to &quot;cross&quot; examine him or her. To what extent is cross examination limited only to subjects brought up in direct examination? Can the cross examiner dig into a bunch of background issues in a witness' past to prove bad character or bias, for instance? Or is there an &quot;intermediate&quot; position whereby cross examination is limited to issues brought up on direct examination, plus certain specific &quot;tangential&quot; issues not brought up previously (e.g. &quot;rape shield laws protect a victim from being asked certain questions).
In the United States, different jurisdictions have different rules about what topics may be addressed in cross examination. In the federal courts, Fed. R. Evid. 611 generally discourages cross examination on matters not addressed in the direct examination, although it also permits questions on &quot;matters affecting the witness’s credibility.&quot; So if a witness is asked on direct examination only about whether A stopped at the intersection before B crashed into him, the cross examination probably shouldn't go into questions about how severe the injuries were, what the weather conditions were, etc. But the court should allow cross-examination on whether the witness is the plaintiff's sister, or whether the witness was previously convicted of perjury. (Despite the rule, the court has a great deal of latitude as to how to handle these questions, practically speaking.) In the state courts, the rules may be different. In Ohio, for instance, Rule 611 is roughly identical, except that it generally allows questions on &quot;all relevant matters.&quot; So now the questions about the weather and injuries are fair game, along with the questions about the witness's credibility. In any event, the questions will remain subject to the other rules of evidence, so questions about sexual history might be excluded by the rape shield, and questions about irrelevant matters should be prohibited, as well.
The answer to this question will be almost entirely informed by the why that you've asked us not to consider. If the prosecutor or judge is a witness, the defendant should be able to call them, but that also means they would have to withdraw from the case under either Rule 3.7 or Canon 3. If the defendant believes the prosecution is tainted by some improper motive, the defendant may raise that objection under Crim. R. 12, but he must do so pretrial. I can't think of any circumstances where the defendant could question the judge or prosecutor in the jury's presence.
The general concept is reporter's privilege, which is a protection against being compelled to testify about confidential information. There is no clear national statute or ruling in the US, but most states have enacted shield laws. Since these are state laws, they vary considerably. It had been thought that the First Amendment protected reporters from having to reveal sources, but in Branzburg v. Hayes, 408 U.S. 665, it was held that The First Amendment does not relieve a newspaper reporter of the obligation that all citizens have to respond to a grand jury subpoena and answer questions relevant to a criminal investigation That 1972 decision is the sum of what SCOTUS has to say about the topic. States then enacted various protections for reporters against compelled testimony. There are specific law requiring certain individuals to report suspected crimes, whereby doctors and teachers have to report certain suspicions or facts when they encounter them in the course of their work. As a subcase of mandatory reporting, in 18 states, everyone is required to report child abuse (but not in California). There are no mandatory reporting requirements for reporters apart from the limited universal requirement pertaining to child abuse. There are widespread laws against aiding and abetting, so if a reporter drove the getaway car, they would be in trouble – almost certainly not applicable to typical cases of investigative journalism. Some states have a law about failure to report a felony, so in Texas, it is a Class A misdemeanor to fail to report. However, the duty is somewhat narrowly limited to one who observes the commission of a felony under circumstances in which a reasonable person would believe that an offense had been committed in which serious bodily injury or death may have resulted Witnessing murder would be covered by this. Ohio has a stronger law, which creates a duty to report any felony. From what I can tell, California does not have such a law. [ADDENDUM] The Reporter's Committee for Freedom of the Press makes available a by-state compendium of legal sources, with case law for all sorts of situations.
Is it possible for a witness to backtrack and claim that their previous statements were wrong because they misremembered? ... Is the witness now allowed to say something along the lines: &quot;Huh. That's odd. I clearly remember it differently. But it's such a small detail and it was so long ago...&quot;? Yes. Or is it now considered a deliberate lie? A judge's assessment of a witness's credibility and reliability is much more nuanced. See &quot;How is a judge to evaluate a witness's credibility?&quot;
In new-jersey, the offence of perjury is defined at 2C:28-1 of the Code of Criminal Justice A person is guilty of perjury, a crime of the third degree, if in any official proceeding he makes a false statement under oath or equivalent affirmation, or swears or affirms the truth of a statement previously made, when the statement is material and he does not believe it to be true. The Code also provides an opportunity for retraction. Assuming that the statement is material, whether answering &quot;no&quot; is perjury will depend on the witness's understanding of the question and his belief about the truth of the answer. If we assume that the witness understands the question to be about parentage in general, including by adoption, and if we assume that they know they have an adopted child, the answer &quot;no&quot; would be perjury. If instead we assume that the witness understood the question to be narrowly about biological parentage, or if they had forgotten at the time of their answer that they had an adopted child, then the answer &quot;no&quot; would not be perjury.
As I understand, the limited liability that police enjoy, requires that people bringing civil cases against police must prove that the police person should have had a reasonable knowledge of the civil rights that you accuse him of breaking, for the civil case to be successful. This isn't quite right. The test you are referencing is the one for qualified immunity from civil liability under 42 U.S.C. § 1983, which imposes liability on government officials only for violating a &quot;well-established&quot; constitutional right. A rule of law is &quot;well-established&quot; when there is controlling case law in that jurisdiction when a factually similar binding precedent exists in that jurisdiction to show that the alleged conduct is unconstitutional. This test is employing the legal fiction that police officers are familiar with all of the binding precedents in the jurisdiction regarding what constitutes a violation of a constitutional right, which is held against officers. Of course, in reality, almost no police officers have that exhaustive a level of understanding of the law. What the test does, however, is to prevent police officers from being held civilly liable for money damages when they take action which, in fact, violates a constitutional right, but which no case law in a factually similar case that was binding precedent established before the incident took place. Thus, police officers are relieved of liability for incidents that they would have to predict that a future court would find violated a constitutional right. This is sometimes phrased as being justified because a reasonable police officer could not have foreseen a new rule of constitutional law or a novel application of an existing rule of constitutional law to a new situation. One of the reasons that the qualified immunity rule is controversial, however, is that courts have the discretion to decide a case on qualified immunity grounds without determining if the underlying action indeed did violate a constitutional right, and this prevents constitutional law from evolving normally over time to applications in new factually novel situations. The key point, however, is that this requirement that a constitutional right be well-established to be enforceable in a civil action is an &quot;objective&quot; test in that it is decided without any reference to what the particular individual being sued actually knew about the law in the particular circumstances presented. A police officer who acts without actually knowing the law does so at his or her peril.
canada Canada has a similar protection. Section 13 of the Canadian Charter of Rights and Freedoms says that: A witness who testifies in any proceedings has the right not to have any incriminating evidence so given used to incriminate that witness in any other proceedings, except in a prosecution for perjury or for the giving of contradictory evidence. The person is protected against the use of their compelled testimony or any evidence derived therefrom in any subsequent criminal proceedings (other than for perjury).
It is not as simple as the witness just making the assertion that they are the killer. They will be subject to grueling cross examination to break their story. If the victim was killed at a specific time, perhaps the prosecution can prove the witness was somewhere else at that time, and therefore lying. (No Opportunity) If the victim was killed with a specific weapon, perhaps the prosecution can prove that only the accused had the weapon, and the witness had no access to it, and therefore lying. (No Means) If the victim was killed in a specific way, perhaps the witness doesn't know any of the details of how the crime happened, and therefore is not credible. (No Knowledge) If the accused's DNA is found at the scene, and their shirt is covered in blood, and the witness has no corroborating evidence against them, then the witness is likely lying. (No Evidence) If the witness claims he is the murderer, the prosecution can inquire as to why he killed the victim. The real murderer had a reason: Perhaps money, power, hatred, passion, etc, that the witness may not be able to provide. (No Motive) Planting doubt in the mind of a jury is an effective defense. But lying about who did what, when, how, and why it is not as easy as you suggest.