501 General rule

Here's what this rule means in plain English:

In general, people don't get to pick and choose whether they testify, answer questions, or hand over documents in court. If you're called as a witness or asked to produce evidence, you have to cooperate unless a specific law or rule says otherwise.

This rule sets up the basic starting point for the whole legal system. Courts need information to make fair decisions, so the default rule is that everyone must share what they know when asked. You can't refuse to testify, refuse to answer questions, refuse to hand over an object or document, or stop someone else from doing these things, just because you'd rather not.

The only way around this is if a specific privilege applies. For example, the Constitution protects you from having to say things that would incriminate you. Other rules protect conversations between spouses, or between a client and their lawyer. But those protections have to come from an actual law, constitutional right, or specific court rule. Without one of those, you don't get to invent your own reason for staying silent or withholding evidence.