The Ninth Amendment simply says the people have more rights than those enumerated by the Bill of Rights. There are two ways of reading this. Some lawyers take the narrow view, that this doesn't confer any additional rights, but is just a hint on how to read the Constitution. Some take a more expansive view, that there are a vast number of human rights out there, waiting to be discovered. For example, some wanted to use the Ninth Amendment to insist "abortion" was a human right in Roe v. Wade. Generally, lawyers take the narrow view, because the expansive view becomes ultimately unworkable when everything is a potential "right".
I'm not a lawyer, but a revolutionary. For me, rights come not from the Constitution. Bill of Rights, or Supreme Court decision. They come from the Declaration of Independence, the "natural rights" assertion, but also things like the following phrase used to justify the colony's revolution:
...when a long train of abuses and usurpations, pursuing invariably the same Object evinces a design to reduce them [the people] under absolute Despotism, it is their right, it is their duty, to throw off such Government...The state inevitably strives to protect its privilege and power at the expense of the people. The Bill of Rights exists to check this -- so that we don't need to resort to revolution every few decades. The First Amendment protects free speech not because this is a good thing, but because it's the sort of the thing the state wants to suppress to protect itself.
In this context, therefore, abortion isn't a "right". Abortion neither helps nor harms the despot's power. Whether or not it's a good thing, whether it should be legal, or even whether the constitution should mention abortion, isn't the issue. The only issue here is how it relates to government power.
Thus, we know that "recording police" is a right under the Declaration of Independence. The police want to suppress it, because it challenges their despotism. We've seen this in the last year, as films of police malfeasance has led to numerous protests around the country. If filming the police were illegal in the United States, this would be an usurpation that would justify revolt.
Everyone knows this, so they struggle to fit it within the constitution. In the article above, a judge uses fancy rhetoric to try to shoehorn it into the First Amendment. I suggest they stop resisting the Ninth and use that instead. They don't have to accept an infinite number of "rights" in order to use those clearly described in the Declaration of Independence. The courts should simply say filming police helps us resist despots, and is therefore protected by the Ninth Amendment channeling the Declaration of Independence.
The same sort of argument happens with the Fourth Amendment right to privacy. The current legal climate talks about a reasonable expectation of privacy. This is wrong. The correct reasoning should start with a reasonable expectation of abuse by a despot.
Under current reasoning about privacy, government can collect all phone records, credit card bills, and airline receipts -- without a warrant. That's because since this information is shared with a third party, the company you are doing business with, you don't have a "reasonable expectation of privacy".
Under my argument about the Ninth, this should change. We all know that a despot is likely to abuse these records to maintain their power. Therefore, in order to protect against a despot, the people have the right that this information should be accessible only with a warrant, and that all accesses by the government should be transparent to the public (none of this secret "parallel construction" nonsense).
We all know there is a problem here needing resolution. Cyberspace has put our "personal effects" in the cloud, where third parties have access to them, that we still want to be "private". We struggle with how that third party (like Facebook) might invade that privacy. We struggle with how the government might invade that privacy. It's a substantial enough change that I don't thing precedence guides us, not Katz, not Smith v Maryland. I think the only guidance comes from the founding documents. The current state of affairs means that cyberspace has made personal effects obsolete -- I don't think this is correct.
Lastly, this brings me to crypto backdoors. The government is angry because even if Apple were to help them, they still cannot decrypt your iPhone. The government wants Apple to put in a backdoor, giving the police a "Golden Key" that will decrypt any phone. The government reasonably argues that backdoors would only be used with a search warrant, and thus, government has the authority to enforce backdoors. The average citizen deserves the protection of the law against criminals who would use crypto to hide their evil deeds from the police. When an evil person has kidnapped, raped, and murdered your daughter, all data from their encrypted phone should be available to the police in order to convict them.
But here's the thing. In the modern, interconnected world, we can only organize a revolution against our despotic government if we can send backdoor-free messages among ourselves. This is unlikely to be much of a concern in the United States, of course, but it's a concern throughout the rest of the world, like Russia and China. The Arab Spring was a powerful demonstration of how modern technology mobilized the populace to force regime change. Despots with crypto backdoors would be able to prevent such things.
I use Russia/China here, but I shouldn't have to. Many argue that since America is free, and the government under the control of the people, that we operate under different rules than those other despotic countries. The Snowden revelations prove this wrong. Snowden revealed a secret, illegal, mass surveillance program that had been operating for six years under the auspices of all three branches (executive, legislative, judicial) and both Parties (Republican and Democrat). Thus, it is false that our government can be trusted with despotic powers. Instead, our government can only be trusted because we deny it despotic powers.
QED: the people have the right to backdoor-free crypto.
I write this because I often hang out with lawyers. They have a masterful command of all the legal decisions and precedent, such as the Katz decision on privacy. It's not that I disrespect their vast knowledge on the subject, or deny their reasoning is solid. It's that I just don't care. I'm a revolutionary. Cyberspace, 9/11, and the war on drugs has led to an alarming number of intolerable despotic usurpations. If you lawyer people believe nothing in the Constitution or Bill of Rights can prevent this, then it's our right, even our duty, to throw off the current system and institute one that can.