Here’s a short article on two cases pending at the Supreme Court, Montejo v. Louisiana and Kansas v. Ventris.
Bidish J. Sarma, Robert J. Smith, & G. Ben Cohen, Interrogations and the Guiding Hand of Counsel: Montejo, Ventris, and the Sixth Amendment's Continued Vitality, Northwestern L. Rev. Colloquy, 3 April 2009.