How is it possible for millions to use pirated software at home and never get arrested? It's not like talking about using weeds that you tell your friends about but you don't go in public shouting about it. Instead people go to online forums sometimes posting with their real names- bragging about using pirated software. What is exactly stopping the police from having them arrested?
Civil law instead of criminal law Not all things that we commonly refer to as "illegal" are actually crimes - many of them refer to violations of contracts or other obligations where the harmed party may (or may not) use the civil system to obtain some satisfaction, but the government and prosecutors will not do it for them. In general (with some exceptions, depends on jurisdiction and circumstances), most low scale copyright violations are treated as a civil matter - it allows the harmed party (i.e. the copyright owner) to sue you for damages in a civil court, if they wish and are able to do so. However, it generally is not a crime (again, with some exceptions - e.g. large scale distribution often is) so the government and police on their own cannot, should not and does not investigate and prosecute violations of software licence terms.
Not all illegal things are crimes. Lack of evidence. They are asked to testify, and they say "what I said in my book was a lie". There is no general law against lying, except when under oath. Statute of limitations. Saying "10 years ago I did smoke drugs" means that any offence is no longer prosecutable. Lack of details. Which jurisdiction were they in? When did they commit the act, how many acts? You cannot be arrested for being a "bank robber" or a "murderer". You are charged with "robbing Bank X on 123 Fake Street the Thursday 25 April 2018" or "murdering Jim Thio in January 2017". Otherwise the defendant would have a hard time defending himself (how to prove that you have not killed anyone at any time?) All of the above combined with prosecutorial discretion in the form that any possible prosecutor will most likely determine that bringing charges would be just a waste of time and resources. UPDATE February 2018: Just for the sake of completeness, a reference to the situation of Jacques Cassandri, who did boast about a serious crime(a robbery in a Societe Generale vault in 1976) in a book. Unfortunately for him, he made some kind of mistake/miscalculation and the crime had not yet expired, so he has become an example of someone being prosecuted by confessing a crime in a book.
Although the USA don't like it, there's a department called INTERPOL which is composed by about 150 countries. When a crime is committed and you need to involve another country to solve it, the sovereignty of each County prevents a police officer from one country acting upon another country. That's when the INTERPOL comes in. They usually requests the police from that country to act up. A judge from that country will grant their local police access to the data to be delivered to the country that requested it. Can the police get a search warrant for data 'in the cloud'? Yes. If the servers are located within the boundaries of your own country, it's a normal procedure. But like the above answer states, it's easier to subpoena the records than to execute a search warrant. In a subpoena, the company itself is bound to provide everything the police asks. Can the police get a search warrant for such third party systems? Yes. If there's enough probable cause, the investigation can lead to allow the police to try and discover files that are held by servers that store the cloud data. But if the servers are located outside the country and the company does not have any office opened in the country, a search warrant won't have validity in another jurisdiction and the police can't act without breaking the sovereignty principle. That's where the INTERPOL services are handy. The department is built in the principle of polices from different countries helping each other. The downside is that it's too bureaucratic and it takes a lot of time. For instance if he has a virtual machine hosted by Amazon, would they serve the warrant on Amazon, or on the suspect? Like mentioned by @Viktor, if the company has an office within the bounds of your country, it's easier to subpoena the records because that way the company will filter and provide only the data linked to the suspect being investigated. That is, the subpoena will have both the name of the company (Amazon) and the name of the Suspect, so the company can provide only the necessary files. Update If the police lack sufficient evidence for a search warrant, but an interpol country was, for some reason, willing to work with the police to collect and provide that information would they be able to use it even if they wouldn't have been able to subpoena a US country? Hypothetically speaking, I see your follow-up as a company that do have a local office and the Federal Police was turned down by a judge on a warrant/subpoena. In that case, there's no reason for another's country police to act on their own country. The suspect is a foreign suspect, the crime is a foreign crime and the police has no reason to work on it. But for the sake of argument, let's say that the local police was turned down by a judge for lack of evidence or something and the suspect has been investigated by a foreign country or whatever. If the information that the local police desires to obtain is available through the INTERPOL, it's most likely to be accepted since it's a data stored by an international police department. In your scenario, the foreign police was granted a legal right to search and collected the data for legal purpose. Maybe they can't use it in their own country, but since they followed a safe chain of custody and provided the information to the INTERPOL, that information has legal validity and it is not fruit of the poisonous tree if the chain of custody was maintained.
This would be unauthorized access to a computer. The offence is found in Section 1 of the Computer Misuse Act 1990. Note that this is a criminal offence, approaching the police about it might be the best way of handling the situation (if you want to go that route, and also, I'm not a lawyer).
I'm wondering whos responsible for this code if people start using it? The user. Can the people using it that think its under GPL in any way get in trouble for it or be made to remove it from their projects? Yes, they can be sued (successfully) for copyright violation. It’s not enough that you think you have permission from the copyright holder - you actually have to have permission. The law places the onus on the copier to seek out and get permission from the copyright holder. In theory, someone deceived in this way could sue the repo poster(s) for misrepresentation, however, there are practical issues about finding them, having them in an accessible jurisdiction and if they are judgement proof. Copyright law was created to protect physical books and paintings - it doesn’t really fit with digital methods of reproduction but it is the law. It doesn’t matter that complying with it can be hard bordering on impossible - comply with it you must.
"Educational use" does not get a free pass on the law against circumventing copy-protection. First, "educational use" is extremely broad and could include "to post on Stackexchange", or "so that I can learn something". The cited clause specifically limits this exception to "A nonprofit library, archives, or educational institution" – the library must be nonprofit, and the archive or educational institution may also need to be nonprofit (until the courts fix the ambiguity in the scope of "nonprofit"). Second, the circumvention has to be very limited: the purpose must be only to evaluate the work, to see if you want to legally acquire it. So a nonprofit library can peek into a work to see if they want to buy a copy, but you may not. The only thing the library can do is evaluate the work for legal acquisition, and they have to get rid of the pirated copy once they've made the decision. Additionally (other parts of the subsection say), they can't do this is there is an equivalent legal copy available (e.g. if there's a print book available, they can't hack into the e-book to "determine" whether they want the book), and w.r.t. libraries and archives they must be open to the public.
It is probably illegal, just not pursued. In the case of something like bank robbery, you'd have a victim that filed a police report. A murder would need to be discovered somehow - either a missing person report or a dead body. If the porn shoot happened somewhere that a member of the public saw it and subsequently filed a police report, the video could be used as evidence. Absent a report, the police simply have no reason to look into it (unless the police catches them in the act, but we probably don't see those videos posted online). Why would these public offenses go unreported? Perhaps nobody sees it. Perhaps the bystanders in the video are paid extras. Maybe they're filming in what appears to be public but is actually private property. Perhaps they have a permit to use a public space for this purpose. Perhaps they just got lucky. Again, there might be some confirmation bias here - you're not going to see as many videos of folks they catch breaking the law, since they will either be interrupted and stopped or (maybe) have their videos ordered taken down.
The legal system is set up to alleviate the problem or conundrum of intimidation by perpetrators. In the US criminal system, the State is the plaintiff, not the individual. In the extant described situation, very likely all you would have to do is sign an affidavit that the recovered phone is your phone, and that it was removed from your possession by unknown means on or about a certain date. From your description given here you don't know if it was stolen...you appear to have perhaps dropped it or left it somewhere, and someone picked it up/found it. Clearly it didn't belong to them, but this is more like "recovered lost property" rather than "received stolen property." The craigslist poster might be entirely un-chargeable with a crime, though they might have to give up the phone to you.