NEW YORK, Oct 28 (Reuters) - A state appeals court upheld the 2009 first-degree murder conviction of a New York doctor accused of hiring a relative to gun down her estranged husband, despite its finding that threats made by the doctor's sister should not have been introduced during her trial.

Mavoltuv Borukhova was sentenced by a Queens jury to life without parole for the 2007 murder of Daniel Malakov, who was shot in broad daylight in front of the couple's four-year-old daughter in a public park near Malakov's dental office in Queens.

During a lengthy and sometimes sensational trial, prosecutors said that Borukhova and Malakov were in the midst of a bitter divorce and custody battle over their daughter when Borukhova paid her cousin's husband nearly $20,000 to murder Malakov.

High-profile defense attorney Alan Dershowitz and his brother Nathan, who represented Borukhova during her appeal, argued that the trial court had made several significant errors -- including allowing jurors to hear threats made to Malakov by Borukhova's sister just three days before the shooting, and statements from an emotional family court hearing when a judge awarded custody of the couple's daughter to Malakov -- that should void the guilty verdict and life sentence she received.

Borukhova's attorneys also protested other issues with the trial. The prosecution was given a full weekend to prepare for its closing arguments, while the defense has to present its summations on Friday morning, to accommodate the defendant's observance of the Jewish Sabbath, and the trial judge, Justice Robert Hanophy, rushed the trial to avoid interfering with his own vacation plans, according to Borukhova's attorneys.

ERRORS WERE HARMLESS

The Second Department agreed that the lower court had made errors, but a unanimous four-judge panel found nothing that warranted overturning the verdict.

"We conclude that while certain statements made by the defendant should have been suppressed by the hearing court, and the testimony regarding the threat made by the defendant's sister should not have been admitted into evidence at trial, these errors were harmless beyond a reasonable doubt, and the defendant was not deprived of her right to a fair trial," the panel wrote.

The statements had not affected the key evidence supporting the jury's verdict, including eyewitness testimony from the shooting, fingerprints linking the accused gunman to a makeshift silencer used on the gun, and phone records showing a heavy volume of calls exchanged between Borukhova and the accused gunman, according to the appeals court.

"Obviously, we're disappointed that the court found a number of significant errors and determined they were harmless," said Nathan Dershowitz, of Dershowitz Eiger & Adelson.

Dershowitz said that he would be discussing with his client a possible appeal to New York's Court of Appeals, the state's highest court.

In a statement, Queens District Attorney Richard Brown called the case "terribly sad."

"The Appellate Division's unanimous affirmance of the jury's verdict and the trial court's sentence of incarceration will hopefully bring a measure of closure to Dr. Malakov's family," Brown said.

The case is People v. Borukhova, in the Supreme Court of the State of New York, Appellate Division, Second Judicial Department, no. 4153/2009.

For the prosecution: Assistant district attorneys Gary Fidel and Donna Aldea.

For Borukhova: Nathan Dershowitz, Amy Adelson, Victoria Eiger, Daniela Elliot and Alan Dershowitz of Dershowitz Eiger & Adelson.

(Reporting by Jessica Dye)

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