> The right of the people to be secure in their persons, houses, papers, and effects, against unreasonable searches and seizures, shall not be violated, and no Warrants shall issue, but upon probable cause, supported by Oath or affirmation, and particularly describing the place to be searched, and the persons or things to be seized.

The 5th amendment

> No person shall be held to answer for a capital, or otherwise infamous crime, unless on a presentment or indictment of a Grand Jury, except in cases arising in the land or naval forces, or in the Militia, when in actual service in time of War or public danger; nor shall any person be subject for the same offence to be twice put in jeopardy of life or limb; nor shall be compelled in any criminal case to be a witness against himself, nor be deprived of life, liberty, or property, without due process of law; nor shall private property be taken for public use, without just compensation.

IMO it's pretty cut and dry that the government can't just seize your stuff on a whim, and was written as a reaction to the British Crown doing exactly this sort of thing.

> No person

This is what the courts have decided to focus on, after the police and district attorneys filed cases against property, and not people.

This is how a monopoly on power acts in absence of constitutional limitations.

I think the first big shift happened with Oliver Wendell Holmes and the move away from originalist interpretation. Arguably this was bound to happened, and will continue to expand further out. The Constitution is honestly just given a nod and has little bearing on law at this point.

So what counts as "unreasonable"?

The larger point, however, is that you can't appeal to the constitution in this case, because it's so ambiguous.

It can’t be theft until after the courts decide who owns it. Then it can be theft.