Stephen B. Cohen (Georgetown) has posted Whom Do You Trust? A Reply to Prof. Kahn Concerning the Knight Case, Also Known as Rudkin Trust, 125 Tax Notes 711 (Nov. 9, 2009), on SSRN.  Here is the abstract:

In his 2008 opinion in Knight v. Commissioner, Chief Justice John Roberts harshly criticized then Court of Appeals Judge Sonia Sotomayor, writing that her approach to the Internal Revenue Code “flies in the face of the statute.” In the August 3 issue of Tax Notes, I argued that Roberts’ criticism of Sotomayor was “logically flawed and unwarranted.” [Judge Sonia Sotomayor's Tax Opinions, 124 Tax Notes 474 (Aug. 3, 2009).] In the September 21 issue of Tax Notes, Prof. Douglas Kahn [Michigan] defended Robert’s criticism of Sotomayor as “persuasive and accurate” and attacked Sotomayor’s opinion in the case and my defense of what she wrote. [Rudkin Testamentary Trust — A Response to Prof. Cohen, 124 Tax Notes 1263 (Sept. 21, 2009).]  I believe that Prof. Kahn’s arguments in defense of Chief Justice Roberts are contestable and perhaps even untenable.