Why Doesn&#39;t The President Just Make Laws? If the President can create Executive Orders -- and those have the full force of the law, why doesn't the President just start making laws? Skip Congress.
The executive can only make laws within the scope of the powers granted to them by the constitution (of which there are very few) or delegated to them by congress. An executive order that oversteps those bounds is void as recent experience has shown.
You have a couple major misconceptions about US law. First, crimes against the person are generally punished at the state level. States are not restricted to any sort of enumerated powers, and can pass any law they want to promote the general welfare unless there's a reason they can't. This is called the "general police power," and it lets them make everything from contract law to laws against murder. The federal government has to justify what gives it the authority to pass a law, and cities and counties have to justify their authority with state law or a state constitution, but a state government never has to preemptively justify why they have the authority to pass a law. States are especially not limited to powers listed in the federal constitution. The US Constitution sets up the federal government. State governments are set up by state constitutions, and derive their authority directly from the consent of the people of the state exercising their right to democratic self-determination. The only powers the US Constitution gives to states are minor technical powers involving state-federal relations (e.g. deciding how their presidential electors are appointed). But as I said, they aren't generally limited to any sort of enumerated powers by their state constitution either. Even the federal government isn't limited to "protecting rights listed in amendments." That's very little of what it does, in fact. Congress has powers listed (for the most part) in Article I and Article IV. It can pass laws banning murder in DC because Article I lets it exercise exclusive jurisdiction (meaning general police power) over DC and over federal enclaves. Article IV lets it exercise general police power over US territories, and pass laws regarding other federal property (I think it has a general police power there too, at least according to current law). The Necessary and Proper clause gives Congress the power to protect its own operations by, for instance, criminalizing the murder of a federal judge. Etc. Where there isn't a clear thing that lets the feds regulate something, they can probably get away with cramming "in or affecting interstate or foreign commerce" in the law, secure in the knowledge that practically everything affects interstate commerce. I'm not sure where you got the idea that laws are passed exclusively to enforce rights protected by the Constitution. They are not. They are not passed primarily for that purpose. Such laws do exist (e.g. deprivation of rights under color of law, which was passed pursuant to the 14th Amendment), but they're protecting you from government infringement of that right.
So can Congress itself just declare someone guilty of insurrection and bar them from standing in elections, without that being considered a bill of attainder? No. Even if it isn't a bill of attainder, the Congress can't do that. Or do they have to delegate the finding of fact (in re insurrection) to another body, e.g. to the judiciary? The issue would be presented when someone ran for public office and their qualifications were challenged, and would be resolved by state and local election officials, subject to judicial review. If that was not done, Congress could nonetheless refuse to recognize a state certification of someone's election on these grounds.
Part of the problem you'll find is that there are so few impeachments in U.S. History (Only 21 articles of Impeachment have ever been drafted, of which only 8 resulted in convictions) and SCOTUS is so selective on cases it chooses to hear, that only one case has ever been heard and that was upheld (Nixon v. United States). In that case, SCOTUS ruled that it did not have jurisdiction to rule on the legal question before it (was the new trial format a proper trial by the senate), but did not have an opinion one way or another to suggest that SCOTUS could not review other cases that come before it. One of the reasons they also haven't is in order to have a legal case in the U.S., the plaintiff must suffer actual harm. More impeachments ended without a conviction than with either acquittal (8), resignation before trial conclusion (4), and expulsion from senate (1, and will never occur again as Congressional office holders are not impeachable following this particular case). Since no harm was caused and courts do not rule on hypotheticals, a case with actual harm (conviction) must occur in order for SCOTUS to even consider hearing the case. Nixon does not bar SCOTUS from hearing more appeals resulting from Impeachment, it only bars those relating to the manner in which the senate chooses to hold the trial.
The witness can go outside and ask questions of the witness’ lawyers So if, for example, Mr Trump chooses to testify to the grand jury he goes in alone - no lawyers. If he wants to consult his lawyers he needs to ask to do, leave the room and consult them. If I were Mr Trump’s lawyer I would be worried that he wouldn’t know when he should do that.
Art. 1 Sect 5 of the Constitution empowers both houses to make their own rules. That means that they can articulate rules regarding what or how you can talk on the floor. It is held that the president of the senate can issue a ruling, and the ruling can be overridden by majority vote. If the Constitution were amended to be more specific about rules of conduct, then some such Senate rules might be unconstitutional and SCOTUS could invalidate the rule. The only specific constitutional requirement on conducting business is that a majority constitutes a quorum.
Yes, the President can certainly veto such a law. Per the US Constitution (emphasis added): Every bill which shall have passed the House of Representatives and the Senate, shall, before it become a law, be presented to the President of the United States; if he approve he shall sign it, but if not he shall return it, with his objections to that House in which it shall have originated, who shall enter the objections at large on their journal, and proceed to reconsider it. This can have a very real effect: legislators are under no obligation to vote the same way on a veto override as on the original bill. The reason the President needs to supply written objections in the first place is that it lets legislators reconsider, see if they're swayed, or see if they think this is a matter where a Congressional majority needs to be respected even if they disagree (they can change their mind in either direction). They can also get a sense of public reaction. And because the threshold for this is "present and voting," it's possible that just more legislators show up. Even if legislators won't be swayed, it still matters for pocket vetoes. That's where the President neither signs the bill nor returns it within 10 days; normally this is equivalent to signing, but if Congress adjourns in the meantime, it means the bill does not become a law. Because "Congress adjourns" is a necessary part of a pocket veto, it's impossible to override the veto (you can't do it if you're not in session). And even when this doesn't apply either, it matters for politics. Example of a futile veto: Public Law 100-4. Passed 406-8 in the House, 93-6 in the Senate. Vetoed; veto was overridden 401-26 in the House and 86-14 in the Senate (note that at least 7 Senators who voted for the bill voted not to override the veto). Example of an effective veto: While technically there was a conference report agreed to by both houses, and it doesn't seem to have had a roll-call vote (my guess is it was agreed to by unanimous consent; side note: many, many laws don't have roll-calls to check on, because they're passed by voice vote or unanimous consent), H.R.10929 from the 95th Congress was passed in the House by a vote of 319-67 and in the Senate by 87-2. After President Carter vetoed it, the House voted on whether to override the veto. The motion to override was defeated 191-206: after the veto, they couldn't even get a simple majority to override the veto of the bill which had been passed by an overwhelming supermajority. I mentioned it above, but the two-thirds threshold is "present and voting." As a general rule, any time you see a fraction of something needed for a vote to succeed in a deliberative assembly, then unless it specifies some other denominator, it's talking about the fraction of members present and voting. Relevant CRS report on override procedure.
You can certainly do so: it's been done many times in the past, and can be done even with a written constitution. The most recent famous example that I know of would be how the Nazi party used the Enabling Act, 1933 and Reichstag Fire Decree, 1933 to amend the constitution by essentially neutering all the safeguards, and used force to ensure that they could stay in power. Julius Caesar's reforms follow in a similar vein. For someone to successfully force change like this, you generally need a political system that is unstable and has no strong (or at least effective) checks and balances. Additionally, you need the support of the military because otherwise they will generally support the existing structure. Other less extreme examples I can think of where a system has changed to another system would be former colonies adopting new constitutions (e.g. Ireland and Pakistan), or where there has been significant change in the country's model (e.g. South Africa). Again, you need support, but this time it is within the existing political and judicial framework.