In an opinion written by Justice Thomas, the Court declined to limit its prior opinion in Dewsnup v. Timm, 502 U.S. 410 (1992), to partially underwater liens, reversing the Eleventh Circuit in two cases and holding that chapter 7 debtors cannot use § 506(d) to void wholly unsecured junior liens. The amounts owing on first mortgage liens exceeded the current market values of the debtors’ homes, leaving the junior liens with no supporting value.