What type of taxes are expressly forbidden by the Constitution?

Answer 1

An ex-post-facto law, is one that is passed that criminalizes previous acts, and punishes the person for it. Such a law was passed by congress a few years ago, and it is surprising that it has not made it to the Supreme Court yet.

Answer 2

Direct taxes

No, direct taxes are allowed..specifically in fact.

In the United States, Article I, Section 9 of the Constitution requires that direct taxes imposed by the national government be apportioned among the states on the basis of population. After the 1895 Pollock ruling (essentially, that taxes on income from property should be treated as direct taxes) this provision made it difficult for Congress to impose a national income tax that applied to all forms of income until the 16th Amendment was ratified in 1913. After the Sixteenth Amendment, no Federal income taxes are required to be apportioned, regardless of whether they are direct taxes (taxes on income from property) or indirect taxes (all other income taxes)

Answer 3

Direct Taxes :Thanks to me Ada