Can the Federal Government Define “Property” For Purposes of Federal Law?

In his most recent post, my co-blogger Randy Barnett writes that “defining marriage — like defining property — is a traditional function of the states.” He continues:

[T]hat is crazy. It would be like saying you “own” your home under the property law of California, but you don’t “own” your home “for purposes of federal law.” Such a dual property system would undermine the institution of property, and the traditional power of States to define property, every bit as much as allowing a dual system of state and federal marriage undermines the institution of marriage, and the traditional power of states to regulate marriage.

But Congress often defines the meaning of “property” for purposes of federal law. See, e.g., 26 U.S.C. § 317(a) (“For purposes of this part, the term ‘property’ means money, securities, and any other property; except that such term does not include stock in the corporation making the distribution (or rights to acquire such stock).”); 26 U.S.C. § 614(a) (“For the purpose of computing the depletion allowance in the case of mines, wells, and other natural deposits, the term ‘property’ means each separate interest owned by the taxpayer in each mineral deposit in each separate tract or parcel of land.”); 21 U.S.C. § 853(b) (“Meaning of term “property” — Property subject to criminal forfeiture under this section includes–(1) real property, including things growing on, affixed to, and found in land; and (2) tangible and intangible personal property, including rights, privileges, interests, claims, and securities.”).

Plus, lots of federal statutes use “property” or similar words without a statutory definition, and courts interpreting those words have approached their interpretation as a question of federal law, not a question of state law. See, e.g., Dowling v. United States, 473 U.S. 207 (1985) (interpreting the National Stolen Property Act as a question of federal law, noting that because “federal crimes, of course, are solely creatures of statute,” the meaning of terms must “pay close heed to language, legislative history, and [Congressional] purpose.”); Gleason v. Thaw, 236 U.S. 558 (1915) (“Congress, we think, never intended that property in the paragraph under consideration should include professional services.”)

I don’t think I have ever encountered an argument that these statutes are unconstitutional, and cases are wrongly decided, because the word “property” cannot be defined for purposes of federal law without “undermining the institution of property.” Rather, I have always thought that definitions are just definitions. As I tell my first-semester 1Ls, legislatures can use words in quirky ways, and they can define them however they like: When a term is specially defined, what matters is the definition the legislature adopted and not the ordinary or expected meaning of the defined term.

Does the Constitution require a different result when Congress drafts statutes, at least for some words? And if so, is there a list available of what the special words are other than “marriage” and “property”? And how far from the core word does this inability to define the term go? For example, if Congress calls the terms “federal marriage” or “federal property,” is that allowed? How about “maredge” or “prawperty”?