What if the law changes after your proces begins? What would happen if there is a law change and those laws had had an influence on your case? Some scenarios, what would happen: The law you are sued for is deleted ... while your process is going before a case is raised against you (what you did was illegal while you did it) after your process is finished (could you question the judgement?) There is a new law ... while your process is going after your process is finished (could you question the judgement?)
Germany If we actually talk about criminal law, your question is answered by §§ 1 and 2 StGB (the German penal code) – official but of course not binding translation: § 1 [No punishment without law] An act may only be punished if criminal liability had been established by law before the act was committed. § 2 [Jurisdiction ratione temporis; lex mitior] (1) The penalty and any ancillary measures shall be determined by the law which is in force at the time of the act. (2) If the penalty is amended during the commission of the act, the law in force at the time the act is completed shall be applied. (3) If the law in force at the time of the completion of the act is amended before judgment, the most lenient law shall be applied. (4) A law intended to be in force only for a determinate time shall be continued to be applied to acts committed while it was in force even after it ceases to be in force, unless otherwise provided by law. (5) Subsections (1) to (4) shall apply mutatis mutandis to confiscation, deprivation and destruction. (6) Unless otherwise provided by law, measures of rehabilitation and incapacitation shall be determined according to the law in force at the time of the decision. (Note that the last section has been voided in part by the Federal Constitutional Court but this is not relevant here.) which is a legal principle given by the German constitution, in particular by Article 103 para. 2: An act may be punished only if it was defined by a law as a criminal offence before the act was committed. To answer your specific questions with the above rules in mind: The law you are sued for is deleted while your process is going In that case you would not be punished. The law you are sued for is deleted before a case is raised against you (what you did was illegal while you did it) Same answer, you would not be punished. The law you are sued for is deleted after your process is finished (could you question the judgement?) You are out of luck. Only if there would be a new decision for an unrelated reason, your punishment would be taken back. There is a new law while your process is going The new law has no relevance at all. There is a new law after your process is finished (could you question the judgement?) Again, no relevance to your case. In another areas of the law the answers to your questions could actually be different but there would be too many cases to consider for a comprehensive answer.
Basically, it is up to the court. The relevant law is the Police and Criminal Evidence Act (PACE). You don't give much in the way of specifics, but it sounds like you confessed something to the police at the side of the road immediately after the accident, and now wish to dispute that confession. If you are taken to court and the police want to introduce your confession as evidence then you (through your lawyer) can ask the court to rule it out. You may be able to do so on a number of grounds. Was the confession properly recorded at the time? Were you treated in an oppressive manner, such that you felt you had to say what the police wanted to hear. Did you think you might get more favourable treatment if you said what the police wanted? For instance, did you think you might be allowed to go home once they were satisfied? Were you given a proper rest, or were you in a mental state that might cause you to say things without understanding the consequences (it sounds like this would be your main argument, but consider the others too). [Edit] If you needed medical treatment that would also be relevant. Were you properly cautioned (that speech beginning "You do not have to say anything...") before the police asked you questions. If you think you may be facing criminal charges then you should get yourself a lawyer sooner rather than later. A lawyer will know all about this and be able to navigate the relevant legal processes on your behalf. A bit of background: back in the 1970s the police frequently attributed incriminating statements to suspects when arrested, such as "Its a fair cop, guv", or "Who ratted on us?". The rules in PACE were made to stop such "verballing".
While you have correctly stated the usual order of events in a trial, the judge has wide discretion to modify the order if it seems that justice will be served. Even in a serious criminal case, the judge can reopen testimony after closing arguments have started if the judge finds that there is good reason to do so. Traffic cases are generally less formal, and the judge will more freely modify procedure to bring out the facts of the case. I have often seen judges at traffic court ask significant relevant questions, and if they are in fact relevant, i don't think you will get far objecting to their begin asked. I am not a lawyewr, but I also have observed several traffic cases in Maryland and in NJ.
A lawsuit would be unsuccessful. Prosecutors have discretion to prioritize whichever offenses they think are most important, and they are generally immune from civil liability. This is a political grievance, and it comes with a political remedy; voters can recall the DA or vote for a new one when his term ends.
Let me give you a simple, even if rather silly example: You take me to a civil court. You tell the judge "gnasher regularly parks his blue car in front of my home, and the color blue violates my sense of beauty. Judge, make him stop it. " A question of fact would be: Is my car actually blue? Not green, or red? And do I actually park my car in front of your home, and do so regularly? A question of law would be: Am I allowed by law to park my car in front of your home, even when my car has a color that you don't like? If this goes to a civil court, the judge would look at it and probably say: "Even if all the facts that 'Gimme the 401' claimed are true, as a matter of law there would be no case for gnasher to answer, since these actions would be permitted by law". If the judge decided that it is illegal to park cars in offensive colours in front of someone else's home as a matter of law, the court would then have to decide the facts: Whether what you claimed is actually the truth. (And while this example is silly, there have been people claiming that the neighbour's use of WiFi interfered with their health. And by law it is illegal to interfere with someone's health, so the facts would have to be examined).
For the same reason you can’t ask the parties to a contract what they meant Legislation, once enacted, stands on its own independent of the people who drafted it, introduced it to Parliament and voted for or against it. These are not the same people in any event and since the legislation might have been passed anywhere between the 13th and 21st centuries, a lot of them will be dead. There’s a fundamental issue of fairness here. The people who are obliged to comply with the law (you and I) can’t ask the politicians so neither can the judges who have to decide if we did. Further, the judiciary cannot interact with the executive or the legislature in this way without violating the principle of separation of powers. Imagine you are charged with a crime and your guilt or innocence turns on the interpretation of the statute. Do you really want politicians who are looking at how the case plays out on Twitter telling the judge which interpretation to use i.e. effectively telling them whether you are guilty or not?
Law is more like sport than mathematics You don’t know how it will turn out until you play the game. If a case goes to trial it’s because at both sides believe they can win. Both sides probably have good reasons for their belief. At least one of them is wrong.
If the case is filed improperly, the opposing party should file a motion to dismiss. If the opposing party merely disagrees with the allegations, they will likely have to litigate to address those differences. The inconsistency is not an obvious case of perjury, because it could just as easily be a clerical error.