Why do statutes of limitations exist? I don't understand: why artificially create a set of deadlines before which one crime or another can be brought to the conviction stage? Why not be able to investigate and prosecute for an indefinite period of time after a crime has been committed? Why encourage criminals to just sit out?
Statutes of limitations go back a long way The law code of ancient Athens had a five year limitation period except for murder and constitutional crimes. According to Demosthenes, these restrictions were introduced to control sycophants (people who made their living as professional litigators) from bringing unjustified lawsuits in the hope of a lucky verdict. As then, Statutes of Limitations exist to protect defendants who are, remember, presumed innocent. The principles on which this protection is based are that: a plaintiff or prosecutor with a valid case should pursue it with diligence, the older the claim or allegation, the more likely evidence is to be unreliable or lost, litigation or prosecution of a long-past wrong may result in more cruelty than justice. Obviously, this is all a matter of degree and different causes of action have different limitation periods. Most civil causes of action have a limitation period of a few months to a few years which runs from when the plaintiff should have become aware (or from when they attain their majority if they were a child) that they suffered damage. The logic here is that people doing their normal day-to-day activities should not live in perpetual fear that someone from the distant past is going to come out of the woodwork to sue them over an incident they can't remember happened if indeed it did happen. Notable exceptions include claims for damage for child abuse which have a much longer limitation period if they have one at all. Minor criminal offences usually have a very short limitation period partly as a spur to efficiency by those required to prosecute them and partly because the punishments are small and courts have better things to do with their time then try and sort out the probity of 15-year-old evidence for a speeding offence. Serious crimes like, murder and sexual assault typically have no statutory limit or they have a limit that can be set aside on application to the court. For example, in New South Wales the default limitation for civil matters is 6 years, however, it is only 1 year for defamation but 12 years if the action is founded on a deed (among other exceptions). For criminal matters, summary offences (magistrate's court jurisdiction and maximum 2 years imprisonment) must be must generally be brought within six-months, however, there is no limit on serious indictable offences.
Once you withdrew the complaint without prejudice, any statute of limitations benefit you obtained from filing the lawsuit evaporated. From a legal perspective, it is as if you never filed at all, except that the lawsuit that was filed proves that you had notice of the claim at the time you filed, so you cannot take advantage of any "discovery rule" that allows a statute of limitations to start running from the date that you knew or should have known of your right to file a lawsuit. In all likelihood, the statute of limitations has now run, although that would depend upon the jurisdiction in which it was filed. Some jurisdictions toll the statute of limitations during a period of minority, but that tolling might very well be insufficient to allow the claim to be filed 20 years later.
No Once a state has accused a person and tried that person for a particular act or set of acts, the state can't later hold a different trial for the same act or acts. That is the Double Jeopardy rule (or the basics of it at least). Some limited exceptions: If a person is convicted and appeals, and the conviction is overturned, the appellate court may order a new trial. *If there is a mistrial, such as a hung jury (jury cannot agree) then there can be a new trial. If an act is both a state and a Federal crime (in the US) then both can have separate trials, and possibly two convictions. If the accused bribes the judge or jury, that trial will not count, and there may be a new trial. If an act is a crime in two different countries, each can have its own trial (but often they don't). If it is later discovered that the accused committed a quite different act than the one s/he was tried for, a new trial for that act may be possible. But otherwise, whether the accused is acquitted or convicted, only one trial for a given alleged crime. The state cannot later change its mind on what to charge the accused with for the act.
There are a lot more differences than this, but if your teacher sums up what he/she means by that sentence. Here, specifically, in Civil Law, the decision of the courts must comply with the laws as enacted, which means there are specific statutes required to make something illegal. Common Law features Stare Decisis which basically means that if Case A is decided in one way, and Case B is a similar Case to Case B, Case B must yield the same decision for all cases in that jurisdiction and lower courts below that court. This means that while statutes (laws) can be made by a legislature, the courts can "make law" by deciding cases. For example, some States in the United States and England and Wales only recently (within the past 30 years) adopted an actual law that made murder illegal? Prior to that murder was illegal under Common Law Murder that had been based on precedence from bazillion cases before that said it's illegal. Nobody bothered to write it down in an actual law. There are several other big differences such as Inquisitorial vs. Adversarial nature of courts, how and when punishments are decided (The famous "Just following Orders" Defense was given in part because of this difference and a lack of understanding over it.), who is the trier of fact vs. who is the trier of law, but as far as what is "Law" this is a good single summation of the difference in a single sentence. But it really shouldn't be condensed to a single sentence.
The prosecutor always has an advocate The prosecutor in a criminal matter is the State. Since the State is an artificial entity it has to act through agent(s) who advocate for it. In Commonwealth countries the State is synonymous with the Crown - I suppose HRH Queen Elizabeth II could prosecute every case personally but she’s a very old lady with a lot of other things to do (this is a joke - the person is not the office).
Its worth actually reading through the law again - they're meant for different categories of drugs - and its worth looking up the relevant laws as a whole. You can't cherrypick which law you charge them under in this case. It depends on what the suspect has in posession, and if you have more serious charges, they're probably going to be preferred unless the prosecution decides to throw the entire library at the suspect and charge them with everything they can, or a larger subset. A quick search on the internet - which shouldn't be taken as legal advice, brings up this link. Category 1 drugs are addictive and seen as therapeutically useless - you shouldn't have any realistic reason to have quantities of it in your posession. Category 3 is drugs with therapeutic use - stuff like codine. You could get a prescription for that, but there's potential for abuse. They're aimed at different classes of drugs - and the confusion is over a misinterpretation of what the law is about. As an aside, this is why you need to usually read more than just a specific statute or law to get what its about.
The courts do not supersede your constitutional rights, although you may believe that you have a constitutional right that isn't actually there. This article discusses the position that "due process forbids convicting an individual of a crime unless the government proves the elements of the charged offense beyond a reasonable doubt". This standard is actually not stated anywhere in the US Constitution, but it has been assumed as an implicit meaning of "due process". It sounds like you were charged with a crime, and there is most likely an applicable statute in your state that is analogous to RCW 26.50.110 in Washington. So you have the right to a trial and the prosecution would have the obligation to prove all of the elements of the crime beyond a reasonable doubt. It also appears that you did violate the applicable law and you were willing to plead guilty, as urged by your attorney. You are correct that you don't technically have to prove your innocence, but there is a practical problem that if the prosecution provides some weak evidence that you violated the law, then the jury might decide that your failure to refute the evidence means that there is no reasonable doubt. The problem is that there is a tendency for jurors to think that the defendant has to create a doubt. States differ somewhat in how they explain the burden of proof to jurors, and you might fare better in a state where the instruction is that "you must be firmly convinced". Since the attorney seems to have said that "the constitution doesn't apply to this", this is a puzzle. I would not assume (though it is possible) that the attorney was incompetent. It is possible that he was speaking of a non-criminal matter, and it is possible that you were talking at cross purposes. There is no legal situation where "the constitution doesn't apply to this", but perhaps "that constitutional limitation doesn't apply to this specific situation". Regardless of what the attorney said, your attorney doesn't violate your rights, even if he gives you bad advice. The actual court might, and then you would have a cause for an appeal. Similarly, if the district attorney reasonably believes that you are a danger to society and is prosecuting you, that is not a violation of your constitutional rights. An improper conviction would be a violation of those rights, although it might take an appeal to get the court to recognize that fact.
Because HRA1998 says so, but it's not an absolute limit and is subject to discretion by the court: (1)A person who claims that a public authority has acted (or proposes to act) in a way which is made unlawful by section 6(1) may— (a)bring proceedings against the authority under this Act in the appropriate court or tribunal, or (b)rely on the Convention right or rights concerned in any legal proceedings,but only if he is (or would be) a victim of the unlawful act. (5)Proceedings under subsection (1)(a) must be brought before the end of— (a)the period of one year beginning with the date on which the act complained of took place; or (b)such longer period as the court or tribunal considers equitable having regard to all the circumstances,but that is subject to any rule imposing a stricter time limit in relation to the procedure in question.