State Supreme Court Justice Robert W. Doyle Thursday instructed jurors to consider Jeffrey Conroy's testimony about an acquaintance, Christopher Overton, only in relation to Conroy's "state of mind" on the night of Marcelo Lucero's slaying - not to consider the testimony as establishing what actually occurred.

Lawyers not involved in the case said that distinction is very subtle. "It means nothing to the average juror," said Jim Cohen, a criminal law professor at Fordham Law School. "I don't think even the lawyers can fully appreciate the difference."

Doyle allowed Conroy's testimony that Overton had said he stabbed Lucero under a complex exception to legal rules on admissibility of so-called "hearsay" testimony.

Q: What is hearsay?

A: Hearsay is when someone testifies to something that another person said outside court, offered as proof that what they're saying is true, Garden City defense lawyer Brian Griffin said.

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Q: Was Conroy's testimony ultimately a victory for the defense?

A: Experts agree that it would have been better for Conroy if the judge had allowed his testimony to go to the truth of what happened, not just to Conroy's state of mind. Ultimately, defense lawyer William Petrillo of Rockville Centre said, the important thing for Conroy is that jurors heard his version of events. Cohen said that Conroy's attorney William Keahon might have an appeal issue in arguing that the judge should have allowed Conroy's testimony to go to the truth of what happened, not just his state of mind.

Q: How much of a risk did Keahon take putting Conroy on the stand?

A: Possibly a considerable risk, Griffin said, because when a defendant testifies, jurors often stop focusing on proof beyond a reasonable doubt and decide the case based upon whether they found the defendant believable. "You're putting all your chips on the table," Griffin said. "It can be the moment that secures the acquittal, or it can be the undoing of weeks of cross-examinations and reasonable doubt."Q: