Judgment, Supreme Court, New York County (Dorothy Cropper, J., at preliminary proceedings; Renee White, J., at jury trial and sentence), rendered November 26, 2002, convicting defendant of robbery in the first degree and criminal possession of a weapon in the second and third degrees, and sentencing him, as a second violent felony offender, to an aggregate term of 17 years, unanimously affirmed.
The court properly denied defendant’s challenge for cause to a prospective juror. Contrary to defendant’s assertion, the panelist evinced an understanding of the jury’s role in assessing the credibility of witnesses, and never stated that she would uncritically accept all sworn testimony. Furthermore, nothing in her responses expressed bias for or against any party, or an inability to follow the instructions of the court (see People v Arnold, 96 NY2d 358, 366-368 [2001]).
Nothing in the record casts doubt on defendant’s mental competence or his fitness to make a valid waiver of his right to be present at his Sandoval hearing, which he refused to attend (see *222People v Morgan, 87 NY2d 878 [1995]; People v Wilkerson, 294 AD2d 298 [2002], lv denied 98 NY2d 772 [2002]). Defendant had been found competent only a few months earlier. Furthermore, he clearly demonstrated his competence both before and after his refusal to attend the Sandoval hearing, and he participated in all other phases of the hearings and trial without incident.
The court properly adjudicated defendant a second violent felony offender. Defendant’s vague and unsupported assertions did not establish that his predicate felony conviction was unconstitutionally obtained (see People v Harris, 61 NY2d 9, 15-16 [1983]). Concur — Mazzarelli, J.E, Saxe, Ellerin, Williams and Sweeny, JJ.