Triggering the investigation is fine and reasonable.
Confiscating the wealth without evidence of a crime is the issue.
Civil Asset Forfeiture in the US is regularly confiscating not tens of millions of dollars, but mere thousands of dollars for the simple reason of it being in cash. And this case is even worse - the cash was not on anyone's person out in public, but in a safe deposit box, not doing anything in particular.
Sometimes the case is never brought to trial [1]; in other cases the owner of the assets is never even charged with a crime [2]. When the forfeiture creates a financial burden [3] or the asset has the potential for depreciation [3], the accused may have even a financial incentive to settle rather than go to trial.
[1] https://news.ycombinator.com/item?id=31446215
[2] https://news.ycombinator.com/item?id=8588268
[3] https://news.ycombinator.com/item?id=10365463
[4] https://cre.org/wp-content/uploads/2017/03/37_2_3_Federal_Fo...
I'd much rather live in a place where that dang mobster that "no one can touch" gets a little rich and evades the law (until that day he doesn't), than to live in a dystopian totalitarian mega-state (e.g. China).
> Is it unreasonable that law enforcement asks how did you aquire an amount of money that is greater than you could ever earn in your lifetime?
Yes, very much so. It's very, very, incredibly dangerous to fall into the trap of allowing a system that asks someone to prove their innocence and that is exactly what your question is asking.
> it's nearly the same mechanism as what was used against alcapone to jail him for income (sic) tax evasion
Nearly the same is not the same. In other words, it'd be OK to check that the $10,000,000 dollar bank account owner did pay taxes on it. If not, well, ooof. But also, how do we know he had a $10M bank account in the first place? That info had better be obtained legally too.
Scenario:
John Doe has 10 million dollars appear in his bank account. No evidence that it was obtained legally and no evidence that any taxes were ever paid.
Option IRS/Alcapone - he goes to jail for Tax evasion
Option 'Unexplained Wealth Order' - UK government seizes assets because they should it could not be obtained legally. He is still free and out and about
If anything the option you are advocating is "worse" as in it is harsher.
Actually, it wasn't that Capone had "an absurd amount of wealth," the amount was irrelevant. Just ask J.P. Morgan, John D. Rockefeller and others who weren't put in jail for being "too wealthy." It was because Capone didn't pay taxes on that income
In fact, the US Internal Revenue Service (IRS) treats "illegal" income[0] exactly the same way it treats "legal" income for tax purposes.
[0] https://en.wikipedia.org/wiki/Taxation_of_illegal_income_in_...
Is it unreasonable that law enforcement asks how did you aquire an amount of money that is greater than you could ever earn in your lifetime?
it's nearly the same mechanism as what was used against alcapone to jail him for inocme tax evasion -> he had access to absurd amount of wealth, and there is no way the could have aquired it legally.