Judgment, Supreme Court, New York County (Felice K. Shea, J.), rendered September 27, 1991 which, after a jury trial, convicted defendant of criminal possession of a controlled substance in the first degree and sentenced him to a prison term of from 17 years to life, is reversed, on the law and the facts, and the judgment is vacated.
It is a fundamental principle that governmental intrusion into the privacy of the home, with very limited exceptions, is prohibited by constitutional limitations in the absence of a valid search warrant (People v Gonzalez, 39 NY2d 122, 127; NY Const, art I, § 12; US Const 4th, 14th Amends; Payton v New York, 445 US 573, 590). One of the exceptions to the warrant requirement is a voluntary consent to search (People v Singleteary, 35 NY2d 528, 532; People v Nalbandian, 188 AD2d 328, lv denied 81 NY2d 890).
The People have the burden, in the first instance, of demonstrating the propriety of the police conduct and "[w]hen a search and seizure is based upon consent * * * the burden of proof [is] heavily upon the People to establish the voluntariness of that waiver of a constitutional right” (People v Whitehurst, 25 NY2d 389, 391; People v Gonzalez, supra, at 128). Further, consent to a search is voluntary when it is a true act of the will, "an unequivocal product of an essentially free and unconstrained choice” (supra, at 128; People v Kuhn, 33 NY2d 203, 208).
In our view, the defendant’s act of glancing over his shoulder at another man inside the apartment, which was apparently in response to the officer’s inquiry if anything was wrong, and which the officer "took * * * to mean” that he could enter