How is an Estate Tax - taxation without representation- constitutionally permissible?

I assume this is a troll, but just in case it isn't: "No taxation without representation" is a slogan from the 1750s that appears nowhere in the Constitution. Accordingly, there is no Constitutional requirement that one must be capable of voting to be taxed. Minors, disenfranchised felons, resident aliens, and corporations are all subject to tax. The decadent doesn't actually pay the estate tax, of course. Their estate does.

Mr. Emeigh is right.  The question also implies that Congress taxes estates through the commerce power.  That is wrong.  Congress's powers to tax estates comes from Article I, Section 8, Clause 1 of the Constitution - the tax and spending clause.    Federal courts have consistently interpreted the tax and spending clause as permitting estate taxes - even before New York Trust Co. v. Eisner, there was the Supreme Court case Knowlton v. Moore, 178 U.S. 41 (1900).  Further, as the Supreme Court notes in Knowlton, the founding fathers in the first Congresses (which included many of the Constitution's framers) passed estate taxes: "As early as 1797, Congress imposed a legacy tax. Act of July 5, 1797, 1 Stat. 527, c. 11. This act was probably the outgrowth of a recommendation contained in a report of the committee of ways and means, presented in the House on Tuesday, March 17, 176. Annals of Congress, Fourth Congress, 1st sess. pp. 993 et seq." As Mr. Emeigh notes, the estate tax - and all inheritance and dynastic wealth taxes - are not taxes on the dead person, they are taxes on the living people who are transferred the assets.  And they've been around in common law countries since the beginnings of republican forms of government - in England since the Magna Carta, etc.

To put most of the previous answers simply, the so-called "death" tax is merely an income tax on those whom receive additional income they would not otherwise gain by inheriting capital provided to them from the deceased's estate. It has nothing to do with constitutional representation for the dead person, and everything to do with income received by the living who have, at least nominally, the right to choose their political representatives via the US electoral process.

This is not a case of "taxation without representation." The taxes are imposed by legislatures, that is, by elected representatives of the people. You referred to "taxation without respiration," by which I think you are saying that the dead person shouldn't be taxed. There are two things wrong with this picture. First, when he was alive, the dead person did have representation in the legislature. Second, it's not the dead person being taxed anyway. That would be meaningless. The tax is on the estate, or on the income received by the heirs.

I paid taxes for 6 years in the US (as a resident alien) but never had the ability to vote. Many foreign corporations pay taxes in the US just because they sell to US residents. Or for that matter any corporation pays tax without the ability to vote. On the other hand, many poor citizens vote without ever paying income tax. I think it is fairly common for someone to be taxed without being represented and vice versa. I don't think there is anything unconstitutional about it.

Taxes have two purposes. The first is to fund the provision of public goods (goods, such as courts or defence, that would suffer from the free-rider abuses if they were provided publicly). The second is to account for externalities that would otherwise distort the efficient functioning of the free market. The estate tax certainly does not serve the first purpose since the owner of the capital has died. It is, however, absolutely critical to the second purpose. With the free market only capable of functioning efficiently if capital is allocated by each individual's best estimate of maximising personal financial gain, and with inheritance having absolutely nothing to do with maximising personal financial gain (again – the capital owner is dead), inheritance is one of the most distorting, anti-free market phenomena in the modern economy. Indeed, it is shocking how many people support the principles of inheritance and still call themselves capitalists. As a result, while it is difficult to make a case for a dead person paying taxes, the case for preventing people from obtaining significant capital exclusively through familial ties is crystal clear. The free market can only function if everyone gets what they earn. Not what their ancestors earned without their involvement. People should not be entitled to the assets of their relatives for the same reason that people should not be obligated to assume those relatives' debts.

Just for clarification: the federal estate tax is a tax on the estate, paid by and from the assets of the estate, not on individuals.  There are no federal inheritance taxes.  States can have both estate and inheritance taxes, or neither.  Inheritance taxes are paid by individuals receiving property from the deceased.  There are huge exemptions from federal estate taxes for spouses and others, such that very few estates actually pay a federal estate tax.  State estate and inheritance taxes and exemptions vary from state to state.

Setting aside the fact that "No taxation without representation" is not technically part of the US Constitution (as it was in the 1689 English Bill of Rights), it boils down to the definition of the word "representation". While representation is often defined as the right to vote, that is not strictly accurate. What it means is that your rights and your interests are represented before the government. Meaning, that there is someone who can go to the legislature to advocate on your behalf. The grievance the American Colonists had was that they were not allowed any direct representation in the legislature. Parliament claimed the Colonists had "virtual representation" meaning that the members of Parliament (which the Colonists had no hand in electing) promised to keep the interests and rights of the Colonists in mind when they made their decisions. Unsurprisingly, the Colonists weren't big on this "seriously guys, you can totally trust us to do right by you" argument. Winding it back around to the original topic, the death tax is not taxation without representation because the best interests of the dead person are considered represented by their survivors, much like how the best interests of a child are represented by their parents. There are a lot of problems with the death tax, and I am personally 100% opposed to it, but this isn't one of them.

The question suggests it's own answer. If the dead can't be taxed, because they have no legal representation, they also don't own property, because they have no legal standing. The dead have no rights in the United States. If we, as a nation, choose to honor their wishes about the disposition of property, it's solely out of respect, not out of rights. Once you stop respirating, your money isn't yours anymore.