The Importance of Evidence even in Constitutional Adjudication

I believe that evidence and inference in law matter because, in important part, accurate factual adjudication matters. It is revealing (and heartening) to see that the Supreme Court, even when immersed in lofty constitutional rhetoric about matters such as separation of powers, also thinks that evidence and the fair assessment of evidence matter. See Boumediene et al. v. Bush, 553 U. S. ____ (2008) (striking down, today, Congress' most recent attempt to strip federal courts of the right and duty to use habeas corpus to challenge the detention of the detainees at Guantanamo):

Petitioners identify what they see as myriad deficiencies in the CSRTs [Combatant Status Review Tribunals]. The most relevant for our purposes are the constraints upon the detainee’s ability to rebut the factual basis for the Government’s assertion that he is an enemy combatant. As already noted... at the CSRT stage the detainee has limited means to find or present evidence to challenge the Government’s case against him. He does not have the assistance of counsel and may not be aware of the most critical allegations that the Government relied upon to order his detention. See App. to Pet. for Cert. in No. 06–1196, at 156, ¶F(8) (noting that the detainee can access only the “unclassified portion of the Government Information”). The detainee can confront witnesses that testify during the CSRT proceedings. Id., at 144, ¶g(8). But given that there are in effect no limits on the admission of hearsay evidence—the only requirement is that the tribunal deem the evidence “relevant and helpful,” ibid., ¶g(9)—the detainee’s opportunity to question witnesses is likely to be more theoretical than real. ...

Although we make no judgment as to whether the CSRTs, as currently constituted, satisfy due process standards, we agree with petitioners that, even when all the parties involved in this process act with diligence and ingood faith, there is considerable risk of error in the tribunal’s findings of fact. This is a risk inherent in any process that, in the words of the former Chief Judge of the Court of Appeals, is “closed and accusatorial.” See Bismullah III, 514 F. 3d, at 1296 (Ginsburg, C. J., concurring in denial of rehearing en banc). And given that the consequence of error may be detention of persons for the duration of hostilities that may last a generation or more, this is a risk too significant to ignore.

A majority of the Supreme Court has today acted courageously.

See my 2006 blog post Here We Go Again: Hearsay, Shmearsay -- Any Good Old Hearsay Is Good Enough for the Commissions