A New Jersey criminal investigator's destruction of notes taken during interrogation of a murder suspect is grounds for a new trial at which the jury will be allowed to draw an adverse inference.

The state Supreme Court held the Middlesex County Prosecutor's Office made a "flagrant" discovery violation by allowing the investigator to scrap the notes after he wrote a formal report.

"The potential for unconscious, innocent self-editing in transferring words, sentence fragments, or full sentences into a final report is a real possibility," Justice Barry Albin wrote in State v. Dabas, A-109-11. "The slightest variation of a word or a phrase can either illuminate or obscure the meaning of a communication."

The court rejected the prosecutor's request to have Samander Dabas' murder conviction, which had been overturned by the Appellate Division, reinstated.

Dabas ran over his 20-year-old wife, Renu, on Aug. 24, 2004, three weeks after she joined him in the U.S. following an arranged marriage in their native India. He was visibly intoxicated after the incident. Prosecutor's office investigator John Dando interviewed him for about two hours before a formal interrogation on tape, during which Dabas implicated himself.

Dando destroyed the handwritten notes from his pre-interview in February 2006 after he prepared his formal report, more than a year after a grand jury had indicted Dabas on a charge of knowing and purposeful murder.

The defense asked for Dando's notes shortly before trial. Superior Court Judge Dennis Nieves refused defense counsel's request for an adverse-inference charge based on Dando's actions.

Reversing, Appellate Division Judges Marie Lihotz and Alexander Waugh Jr. said the requested instruction could have led the jury to accept Dabas' assertions that he did not act knowingly or purposefully, perhaps leading to conviction on a lesser charge.

In Tuesday's ruling, Albin said the destruction of Dando's notes was even more egregious in that it occurred after the indictment. At that point, he said, the prosecutor's office had an affirmative obligation under the discovery rules not only to retain those notes but to supply them automatically to the defense without waiting for a request.

"After a defendant's indictment, as part of its discovery obligations, the prosecution is obliged to provide to the defense any statement made by the defendant that is memorialized in a police officer's notes," he said. "Our discovery rule and case law are crystal clear on this point. Moreover, we have warned prosecutors that we strongly disapprove of the destruction of interview notes, even earlier in the investigative process.

"We sent that message with the expectation that law enforcement officers would preserve their contemporaneous notes of witness interviews."

In State v. Cook, 179 N.J. 533 (2004), the court said destroying notes was a common practice "but one that we disapprove of." And in State v. Branch, 182 N.J. 338 (2005), it said: "We register our displeasure that police officers engage in the seemingly routine practice of destroying their contemporaneous notes of witness interviews after the preparation of formal reports."

It was not until State v. W.B., 205 N.J. 588 (2011), that the court said police officers may not destroy their notes. If they do destroy notes, the cure is the adverse inference ruling.

During oral arguments in March, Assistant Middlesex County Prosecutor Nancy Hulett said officials in her office were aware of the court's statements in Cook and Branch at the time of Dabas' trial but viewed them as dicta.

"[T]he prosecutor's office is not at liberty to disregard a pronouncement of this Court, even if that pronouncement is properly characterized as dictum," said Albin, himself a former assistant prosecutor in Middlesex.

Dando's notes could have changed the outcome of Dabas' trial, Albin said.

"Whether the precise words uttered by Dabas during the two-hour pre-interview were fully and accurately incorporated into Dando's final report, just as they appeared in Dando's handwritten notes, can now never be known," he said. "By shredding those notes, Dando destroyed evidence — the best evidence of what Dabas said during two hours of interrogation. Because of the flagrant violation of the discovery rule, we hold that the trial court erred in denying the defense an adverse-inference charge."

Albin said the ruling would not be applied retroactively in other cases because the court, in W.B., had given law enforcement 30 days to comply with a new mandate. This case, he said, was decided based on the violation of existing postindictment discovery rules.

"Defense counsel did not have to request discovery that the prosecutor was obliged to produce, nor did defense counsel have to possess the foresight that one of the prosecutor's investigators was withholding interview notes of statements made by Dabas and intended to destroy them," he said.

Dabas' lawyer on the appeal, Assistant Deputy Public Defender Marcia Blum, says the court is emphasizing the need for law enforcement to retain handwritten notes. "They were told twice before to not do this, and they did it anyway," says Blum. "These notes can contain information that is highly relevant at trial."

Officials from the Attorney General's Office, which participated as amicus, did not respond to requests for comment. Acting Middlesex County Prosecutor Andrew Carey also did not return a telephone call.

Justice Helen Hoens did not participate.