Kidnapping if two children run away, and one turns 18? So let us say that if there were two minors that ran away together. If one of them turns 18 after they have run away, could the 18 year old be arrested for kidnapping?
"Kidnapping is the unlawful taking away or transportation of a person against that person's will" The crime would occur if the second person was taken by the first, the age of the perpetrator is immaterial to the commission of the crime but it will affect where and how it is prosecuted. The age of the victim will matter as the victim must be old enough to competently grant consent - if they are too young to do so then it will be a kidnapping. On the face of it "running away together" does not imply an unwillingness. Note also that kidnapping is the crime of "taking away"; holding a person against their will is the different crime of false imprisonment.
You don't know. You can't know. And you can't force the officer to tell you. Detention Status As a practical matter, you have no way of knowing if you are compelled to follow an officer's order because you are being detained unless the officer volunteers that information (your detention status) which they are not compelled to disclose and have every incentive not to disclose. Consider the situation when the officer does not have reasonable suspicion do detain you. If the officer instantly informs you that you are "free to go" then you are likely to leave and end the encounter immediately. However, if the officer says nothing, then you might stay and inadvertently say or do something that would give the officer reasonable suspicion to detain you from that point forward. Your behavior during that detention could lead to probable cause, arrest, etc. Every officer knows they have nothing to gain by being quick to tell you you are free to go. Deceptive Conduct To compound the issue, police encounters are particularly problematic because police officers have a lawful right to engage in deceptive conduct during an investigation including but not limited to lying. You, on the other hand, can be prosecuted for lying to the police conducting an investigation. (See this article for more information.) Hobson's Choice Therefore, all things considered, police encounters present a Hobson's Choice. Either comply with every order in an effort to end the encounter quickly. Or try to press the officer to determine whether you are "being detained" or "free to go." The former course of action voluntarily cedes some of your rights. The latter risks "provoking" the officer into making your encounter more difficult, painful or costly than it otherwise might be. Never Consent to Searches That said, you are never under any obligation to consent to a warrantless search of your home or vehicle. Typically, saying, "I do not consent to searches." is usually sufficient if asked. Evidence obtained from warrantless searches is barred from being used at trial unless you waive this right by consenting to the search. See this question (and answers) if you are concerned about the officer falsely claiming you gave consent if you didn't. Never Talk to the Police As a legal matter, talking to the police can never help your case in court. Anything you say to the police that might help your case (i.e., exculpatory) is not admissible as evidence because it's hearsay. On the other hand, anything you say to the police can and will be used against you. In fact, even if you are completely innocent of all crimes AND you are completely 100% truthful to the police, you can still give the police all they legally need to convict you of a crime simply by talking to them. Whereas, without your statement, they would not have had sufficient evidence to convict. See this Youtube video for more details and examples of how this can and does happen every day. Practical Matters The above analysis presents the reader with some practical concerns. You don’t want to risk being harmed by an officer in fear for his safety. You don’t want to be handcuffed and taken to the police station if you can avoid it. You must obey all unconditional commands of a peace officer. It does no harm to inform the officer that you are willing to comply with all unconditional legal commands and ask him or her if a given command is, in fact, unconditional. Some attorneys go in the opposite direction from the "never talk to the police" rule and advise that, say in the case of a domestic violence dispute, the best course of action is to answer police questions matter-of-factly, never lie and never admit guilt. That course of behavior can avoid a potential trip to the police station in handcuffs in the back of a police car even if you are never ultimately arrested. TL;DR: Police encounters are tricky. It's difficult to know what to do. The best course of action is to educate yourself about your rights and the law and apply judgment and common sense to guide your behavior to achieve the best outcome. I am not an attorney. I am not your attorney. This answer is not legal advice. Please consult an attorney to obtain proper legal advice.
In the US, police do not put a person under house arrest, instead, the courts do, as an alternative to standard imprisonment (either awaiting trial, or serving their sentence). The police are not involved at all; the courts cannot be sued for lenient sentencing. If a person leaves their house (even to buy a bottle of milk), they will have violated the terms of their more lenient sentence, and will be arrested and sent to regular jail. Generally, police are not liable for damages, especially when they fail to be omnipotent in their efforts to prevent others from doing wrong.
It is illegal to threaten to report a person for violating the law (it is illegal to threaten a person). There are laws in California that limit official cooperation with ICE investigations, therefore the police will not arrest a person for being an illegal immigrant. This is basically a limit on use of state and local resources, and the state has the power to control its purse strings. The state has no power to mandate that individuals not report a suspected or imagined violation of federal law to federal authorities, and there is no California law purporting to have that power.
It is not entrapment because entrapment must be done by officers of the State (police usually). A member of the public inducing another to commit a crime is not entrapment and not a defense to having committed it. Entrapment is a "thing" in Ireland as it is in all common law jurisdictions, however, the specific limits on what police can and cannot do vary by jurisdiction. Police posing as underage children to catch pedophiles is legal throughout Australia (i.e., not entrapment). Police are more restricted in Canada and the USA but I believe that online "trawling" by police is legal in those jurisdictions too, however, they must remain more "passive" than Australian police. Yes, there is a crime being committed, the crime of attempting to engage in underage sex. It doesn't matter that the actual crime attempted is impossible to commit because the "victim" is not actually underage. Evidence is evidence – it doesn't matter who collects it. However, amateurs in the handling of evidence are more likely to botch it up in a way that would allow the defense to have it ruled inadmissible than professionals (although even they can botch it up).
Desuetude is the wrong concept. Desuetude relates to laws as a whole falling out of use; it doesn’t relate to individual cases. There is no question that the UK actively enforces their bail laws so they are not falling out of use. There is a statute of limitations that applies to non-major crimes within which the state must initiate prosecution. However, in this case the prosecution for bail violation has been initiated and Mr Assange is “on the run” so this is not relevant. Neither is the fact that the original charges that led to his arrest has been dropped- he is wanted for escaping lawful custody under English law for which the penalty is pretty stiff. I will also venture an opinion that the case against him is as open and shut as it comes. TL;DR When he dies.
I'm no expert, but I had assumed this clause was present in case of the following situation. Joe is arrested for a robbery of a London bank. Joe says nothing under questioning. At trial, Joe's defense is that at the time of the robbery, he was in Sheffield drinking beer with his brother. On the basis of common sense, a jury could think: "Surely if Joe were really innocent, he would have told the police of his alibi at the time he was questioned, and saved himself a lot of trouble. Since he didn't do that, maybe a more likely explanation is that he wasn't actually in Sheffield, but that sometime between arrest and trial, he came up with the idea of faking an alibi in Sheffield, and convinced people to testify falsely to that effect. Yes, that does seem more plausible. So we are not going to give much credence to Joe's supposed alibi." So it really would be the case that not mentioning the alibi during questioning would harm Joe's defense at trial. The warning, then, is intended to keep Joe from doing this inadvertently. If Joe's alibi is genuine, but out of a misguided desire to exercise his right to remain silent, he doesn't mention it during questioning, he may accidentally increase his chances of being wrongly convicted. Everybody has an interest in avoiding this.
There's the question whether something is lost property or abandoned property. You'd be allowed to keep abandoned property, but keeping lost property without looking for the owner is in many places considered theft. A car on your land is quite likely abandoned by the last driver (people don't usually lose cars). But the question is whether it is abandoned by the owner; if the car looks like it has some value then it is unlikely to be abandoned by the owner and more likely that it has been stolen. I'd report the car to the police; then it's up to them to find the owner or not. If they can find him, and the car was not abandoned, but actually lost (unlikely) or stolen (more likely), you have the satisfaction of being an honest person helping either a very stupid car owner or a crime victim to get their property back. If they can't find him, usually the property will then belong to the finder.