Good morning everyone,
I Have had an Idea That I think has never been implemented by governments to fight cash evasion
I'm from Italy and here is a quite big problem [1]

This idea also allow to maintain high limits on cash payments to those who still seems to not live without cash..
but to kill 100% -> and I mean really 100% of cash-tax-evasion

THE IDEA IS : put an expiration/validation system on cash bills (maybe only those bigger than 1€ )

:: HOW TO DO IT ::

1) - obviously it would not be convenient to throw away the banknotes so the banknotes are "revalidated" in a database of the state that contains the banknote number and the expiry date.

2) - to revalidate the cash just "photograph" ( maybe in future if this works the bills may have a qr code for a better digitalization ) it with an app for smartphones or specially created tools that follow the same principle of scanning and sending that can also be integrated into special counterfeit banknote detectors or go to the bank with banknotes every MAX 2 years for perform the operation at the counter

3) - the payment operators can equip themselves with a machine that validates the cash (which will probably be like a counterfeit money detector but which moreover read the serial number and validate it (send it to the ministerial database)

4) - expired cash is no longer valid, it can be re-enabled only at a bank by presenting identity documents of those who deposit (or could be worth 40% less than the nominal value creating a kind of "forced tax on the black" ( or read *6 )

5) - during validation (through specific machinery / mobile app / bank counter) the cash is tracked and associated with the validating entity (in this way an operator / private individual will not validate cash for third parties without then declaring it in the balance sheet)

6) - the "expired" cash is worth 40% less every two years ( so after 4y is worth *0.6*0.6 and so on ) , and the expiry date cannot be verified (only bank can verify during a deposit ) but only validated during the taking in charge of the banknote during a transaction., only in this way this system work (otherwise a parallel market of expired currency could arise)

... you can build a blockchain around that system if you prefer :)

:: PROBLEMS & SOLUTIONS ::

7 ) single-state database would be not enough ..
because in Europe there is a single currency shared between more states.. this way new-entry of cash may seems expired.. in this case, however, until the system is implemented at European level it is possible to monitor the flow of "unregistered" cash that a merchant acquires during the activity, and still allow checks on individual cases that become suspect, or the merchant is required to verify the identity card of a foreigner who pays cash in excess of X, everything would still be very effective because the amounts collected in Italy in cash from a foreigner are traced at least in the receiving part and from there on money enters the validation round

you can in the case put a limit on the cash-transaction ( credit card is ok )  used for foreign purchases in Italy with "expired" cash which is much more effective and less limiting than putting a low limit on all purchases in cash , this is a quite low limit anyway circulating with large amount cash ( expecially between countries ) is already forbidden and dangerous..



thank you everyone for your comments,


[1] https://www.bloomberg.com/news/articles/2019-09-17/italy-weighs-penalty-on-cash-withdrawals-to-fight-tax-evasion