In a full-fledged opinion by Judge Graffeo, the Court of Appeals, over a dissent, declined to apply the harmless error rule to a guilty plea. In this driving-while-intoxicated case, the defendant moved to suppress an open bottle of rum and a crack pipe which were found in the car he was driving during an inventory search. The motion was denied. Defendant told the court he wanted to plead guilty because he “was not planning to go to trial if [he] got a negative ruling” on the motion. On appeal, the inventory search was deemed invalid, but the Appellate Division ruled the error “harmless.” In reversing, the Court of Appeals wrote:
The harmless error rule was “formulated to review trial verdicts” (People v Grant, 45 NY2d at 378). It requires an appellate court to assess the quantum and nature of the People’s proof of guilt independent of erroneously admitted evidence and the causal effect, if any, that the introduction of that evidence had on the fact finder’s verdict … . Harmless error therefore can be “difficult to apply to guilty pleas” — especially in cases involving “an improper denial of a pretrial motion to suppress” — since “a defendant’s decision to plead guilty may be based on any factor inside or outside the record” (People v Grant, 45 NY2d at 378379). Consequently, convictions premised on invalid guilty pleas generally are not amenable to harmless error review (see id.).
The Grant doctrine is not absolute, however, and we have recognized that a guilty plea entered after an improper court ruling may be upheld if there is no “reasonable possibility that the error contributed to the plea” (id. at 379). Although a failure to suppress evidence may detrimentally influence a defendant’s plea negotiations, a concession of guilt may be treated as valid if the defendant articulates a reason for it that is independent of the incorrect pre-plea court ruling (see id. at 379-380) or an appellate court is satisfied that the decision to accept responsibility “was not influenced” by the error… . * * *
Certainly, there may be instances where the failure to grant suppression does not affect a defendant’s decision to plead guilty because the challenged proof is cumulative or too trivial. In this case, however, the denial of the motion to suppress could not be viewed as harmless and the guilty plea must be vacated. People v Wells, 188, CtApp 11-14-13