Is the DA bound by agreements made during hostage negotiations? I've seen several fictional situations where a District Attorney agrees to not prosecute various crimes committed by a kidnapper while conducting hostage negotiations. Would an agreement made by a DA in furtherance of obtaining the safe release of hostages be enforceable?
No, this is duress. In 1988, James Harvey took 60 people hostage at the West End Christian School in Tuscaloosa, Alabama. The incident ended when Governor Guy Hunt offered him a video pardoning him. The video was made under duress, and they never had any intention of honoring it. https://en.wikipedia.org/wiki/West_End_Christian_School_hostage_crisis As far as I can tell, Mr. Harvey is still in prison for this incident.
Maybe, maybe not. The answer is implicit in the restraining order, which I assume you have a copy of. If the wording is unclear, you can ask your attorney. The order will state the consequences for violating the order, so you have some idea what the risk factor is. A person may also petition for a new restraining order to include bill-paying, which may or may not be granted.
Miranda rights do not attach until the suspect is subject to custodial interrogation. "Custody" means that the suspect reasonably believes that he is not free to leave the conversation. "Interrogation" means that the officer is engaging in direct questioning or other conduct that would reasonably be expected to elicit a response. A suspect is free to waive his Miranda rights and begin speaking without a lawyer, but a waiver must be knowing, intelligent and voluntary. "Voluntary" means that the waiver is obtained without coercion (torture, threats or promises) by the government. None of the five scenarios indicate that Clyde ever believes he is in custody, so he has no Miranda rights in any of them, making his confession admissible in all of them. But to play it out further, let's assume that Officer Olivia arrives and immediately slaps handcuffs on Clyde: No interrogation, no Miranda rights. The confession is admissible. No interrogation, no Miranda rights. The confession is admissible. Miranda rights attached at the beginning of questioning. Clyde waived by confessing. Reading the Miranda rights established that the waiver was knowing. We don't have any facts suggesting the waiver was not intelligent. The waiver was not obtained by government coercion, so it was voluntary. The waiver was effective, so the confession is admissible. Same as 3. No interrogation, no Miranda rights. The confession is admissible. The key thing to keep in mind here is that the purpose of the Fifth Amendment right against self-incrimination was to avoid misconduct by the government, and it has generally been implemented only to that end. The key case here is Colorado v. Connelly, 479 U.S. 157 (1986), which involved a guy who approached a police officer and asked to talk about a murder he had committed. The officer Mirandized him, and he told them all about the murder and where he buried the body. It turned out that he was a chronic schizophrenic and was going through a psychotic break at the time of the confession, which he had only offered because "God's voice" told him to. As with your truth serum scenario, the question became whether the Miranda waiver satisfied the voluntariness requirement. The Colorado Supreme Court held that "capacity for rational judgment and free choice may be overborne as much by certain forms of severe mental illness as by external pressure." But the U.S. Supreme Court reversed, holding that neither the defendant's due-process rights nor his right against self-incrimination are offended by non-governmental influences, even when they undercut the defendant's free will. Since then, other courts have relied on Connelly to hold that voluntariness was not defeated by: a suspect's flu, hangover, hunger, or exhaustion, U.S. v. Elwood, 51 F.3d 283 (9th Cir. 1995); a suspect's heroin use, Elliott v. Williams, 248 F.3d 1205, 1213 (10th Cir. 2001); a suspect's heroin withdrawal, U.S. v. Kelley, 953 F.2d 562, 565 (9th Cir. 1992); a suspect's orders from his father, N. Mariana Islands v. Doe, 844 F.2d 791 (9th Cir. 1988); or a suspect's unusual susceptibility to suggestion or intimidation, U.S. v. Guerro, 983 F.2d 1001, 1004 (10th Cir. 1993). tl;dr: Because the truth serum was not administered by the government, the confession is admissible in all five scenarios.
In California, all parties to a conversation (people being recorded) have to agree to a recording. There are no special rules pertaining to husbands and wives. It is sufficient that the parties are aware that the recording is being made and they continue to talk, knowing that fact. There are exceptions, under Cal. Penal 633.5, in that surreptitious recordings are allowed in order to gather evidence of "extortion, kidnapping, bribery, any felony involving violence against the person, or a violation of Section 653m". To be used as evidence, there are also "predicate rules" to the effect that you have to prove who the voices are from, that the recording hasn't been altered, and that the recording is reliable (e.g., there isn't a mysterious 18 minute gap).
The validity of the NDA is not an easy question, but a related one is more clear. A lawyer in the U.S. in most states is not permitted to threaten criminal or administrative action (e.g. reporting someone to immigration or tax officials), to gain advantage in a civil case. You can unilaterally bring criminal charges or take administrative action, but it is deemed to be unethical and against public policy to refrain from bringing criminal charges or taking administration action to gain civil advantages. An NDA of the type described arguably violated the same public policy and might be invalidated as a result. Put another way, there is a privilege to make certain reports to public officials without legal consequences and such an NDA might violate that privilege. Some of these privileges found in what are called "whistle blower" statutes specifically prohibit this kind of agreement as to some specific kinds of illegal conduct, but not others. There isn't a general rule. This said, it is not black and white. For example, a private NDA can't prevent someone from testifying under subpoena, but can prevent someone from voluntarily testifying in the absence of a legal compulsion to do so such as a subpoena. Suppose a woman is sexually assaulted at work, and is given an NDA to sign. Can the company legally require her not to disclose the conduct of an illegal activity? I can imagine this example coming out different ways in different jurisdictions. For example, some states have a legal duty (rarely enforced) that requires people to report felonies, and an NDA in this case would contradict that affirmative legal duty, while others do not. Another source of gray in the analysis is that there is a difference between not reporting a sexual assault that actually happened, and, as part of a larger settlement, executing an affidavit stating under penalty of perjury and under oath that a sexual assault didn't happen. The first is potentially an NDA that is void as a matter of public policy. The other, in principle, is a settlement that the person signing the affidavit can only enter into if it is true. There is nothing, in general, wrong, about requiring someone to confirm that certain representations are true as part of a business transaction or contract and allowing the contract to go forwards only if certain facts are true. The gray gets deeper, because whether a sexual assault happened or not is not always a subjectively black and white clear issue of pure fact. (It is subjective because an affidavit or affirmation is made to the best of the declarant or affiants' knowledge and belief, not as a matter of objective fact.) For example, someone may not have perfect memory of what happened, or there could be doubt over the question of whether the perpetrators acted recklessly (the Model Penal Code intent requirement for sexual assault) or merely with criminal negligence (which would not be sexual assault under the Model Penal Code). A statement made under oath about whether a sexual assault happened to the best of your knowledge, thus, might be a mixture of factual issues (A penetrated B at a certain date and time) and legal or not perfectly factually known ones (A acted with X intent regarding consent during that act). So, in a case where there was some room to argue either way about how to characterize what happened and about what actually did happen, there might be some room for a settling party to make a non-perjured statement consistent with the settlement and then to agree not to a true NDA, but instead to not make statements which, if the affidavit is true, would be false. In a plea bargain in a criminal case, one can plead "no contest" without agreeing that the crime factually happened, but that isn't really possibly in the context of an affidavit about what really happened, with an NDA limited to not disclosing the incident since it was already agreed as a matter of sworn fact that there is nothing to disclose that rises the level of a crime.
The legal hook is reported to be §129 of the Code of Criminal Procedure, which authorizes use of force to disperse an illegal assembly, which this sort of is. No statute that I can find states that police can smack lawbreakers who are forced to disperse, but as is common in common law countries, the laws of India are not fully explicit on that which is allowed or forbidden for police to do. As this article indicates, systematic limits on police use of force remain to be developed.
This negotiation tactic is not a crime, but it does implicate an ethical rule for attorneys, Rule of Professional Conduct 4.5, which exists in some states, but has been dropped from the national model rules promulgated by the American Bar Association and is a controversial matter from state to state with several variant forms in different states. In Colorado, the relevant rule of professional conduct for lawyers (Rule 4.5 Threatening Prosecution) states: (a) A lawyer shall not threaten criminal, administrative or disciplinary charges to obtain an advantage in a civil matter nor shall a lawyer present or participate in presenting criminal, administrative or disciplinary charges solely to obtain an advantage in a civil matter. (b) It shall not be a violation of Rule 4.5 for a lawyer to notify another person in a civil matter that the lawyer reasonably believes that the other's conduct may violate criminal, administrative or disciplinary rules or statutes. The concern about the statement in the question is that mentioning that certain allegations would be put in a publicly filed complaint is an implicit threat to expose criminal acts of the other party if the other party doesn't cooperate, but to refrain from doing so if the other party cooperates. This violates Rule of Professional Conduct 4.5(a) above, and goes beyond Rule 4.5(b) above which states that it is not improper to simply tell someone that it may have been illegal and a crime to do the things that he did. The critical distinction is the implied promise not to disclose these crimes publicly if the other party cooperates by not filing the proposed complaint. Under Rule 4.5, a lawyer can tell someone that certain conduct is probably illegal, and can unilaterally report illegal conduct, but can't hold open the possibility of not reporting illegal conduct to gain a civil advantage. The theory is that it is contrary to public policy for a lawyer to put himself or his client in a position where he is promising to help cover up a crime or other violation of the law. This is controversial, and is not adopted in all states, because it makes some very subtle distinctions that often hinge on strongly implied concepts, and that it provides benefit when applied in many cases to someone who has broken the law, instead of making their violation of the law something that makes them worse off in civil cases as well as in other contexts. There is not a counterpart to Colorado Rule of Professional Conduct 4.5 in the Rules of Professional Conduct of New York State, New Jersey, or Florida. So, to the extent that this conduct is subject to ethical rules in any of these states, it would only be indirectly through, for example, through Rule of Professional Conduct 8.4 in each of these states, which is a general catch all clause prohibiting lawyers from committing culpable crimes or that is dishonest or that is prejudicial to the administration of justice. Rule 8.4 is the counterpart for lawyers of the substantive offense in military justice that a military officer has failed to comport himself as an officer and a gentleman. The history of the decision to remove an express prohibition on threatening prosecution from the ethical rules for lawyers is explained in a 2008 ABA article that also discusses how liability might arise under Rule 8.4. In general, there is nothing wrong with making threats in a negotiation. Often that is precisely what negotiations are about. What is (arguably) wrong is making criminal, administrative or disciplinary charge threats in a civil lawsuit to gain advantage in a civil lawsuit. A prosecutor is perfectly free to make those threats in a criminal case, for example. Similarly, it is perfectly acceptable to make a threat of civil legal action, such as filing a lawsuit, in a civil matter, so long as it doesn't imply a threat to bring criminal, administrative or disciplinary charges if the other side doesn't cooperate. Whether it is proper for an attorney to do this depends heavily upon the state in which this negotiation is taking place, which is not identified in the question.
D should be subpoenaing anything and everything they need from anyone and everyone, including E. No matter how good terms you are on, if you are involved in a lawsuit you should not be relying on anyone's good faith to supply you what you need. Suppose you ask nicely and they say yes but, for whatever reason, they don't supply them by your court date. Without a subpoena, if you ask for a continuance the judge will say "tough t*^%^$s"; with a subpoena they will say " Yes certainly, oh, and Mr Sheriff, here is a warrant for the documents, go and get them for me please. Oh and a warrant for the arrest of the person who ignored my subpoena." Where do you want to be?