Act no. 321/2016 Coll.
With effect from: 1 December 2016
As of the day of effectivity of this Act the Financial Authority of the Czech Republic shall get the authorization of verification of the amount of assets of tax payers in connection with the tax return.
In case of suspicion that there is a difference between an increase of assets of the tax payer and his or her reported income higher than 5 million CZK, the Financial Authority is entitled to ask this tax payer to prove the source of such assets or to tax such assets, respectively.
The tax payer is obliged to establish the due sources of his or her assets as required in the formal notice sent by the Financial Authority, unless he or she proves that these incomes were made after the term for determination of tax had already passed. Such term is generally 3 years since expiration of the period for filing of the due tax return (open the official wording).