On Oct. 16, the Supreme Court will hear oral arguments on a claim brought by husband and wife Brian and Kerri Kaley. The Kaleys are asking the high court to answer a serious and hotly contested question in the federal criminal justice system: Does the Constitution allow federal prosecutors to seize or freeze a defendant's assets before the prosecution has shown at a pretrial hearing that those assets were illegally obtained?

Such asset freezes often prevent a defendant from hiring the trial counsel of his choice to mount a...