Donatila O'Mahony of Central Islip, charged with killing longtime friend, goes on trial a second time

A young widow with a gift for manipulation killed a Lynbrook man and later forged his will while persuading others to help her, prosecutors told a Suffolk County jury at the start of a murder trial in Riverhead Monday.

Donatila O’Mahony, 42, of Central Islip, is on trial for a second time in the March 2020 killing of Lee Pedersen at his second home in Aquebogue. An earlier attempt to prosecute O’Mahony ended in a mistrial last October, after a juror was dismissed by Supreme Court Justice Timothy Mazzei for recognizing a relative of the victim outside the courthouse.

O'Mahony, who has pleaded not guilty, is charged with second-degree murder, second-degree possession of a forged instrument and second-degree attempted grand larceny. She faces up to 25 years in prison on the murder charge.

In his opening statement before Mazzei Monday, Assistant District Attorney Frank Schroeder told the jury that he intends to show how O’Mahony used her relationship with Pedersen, 69, to put herself in a position to inherit both his houses.

“This was a horrific crime,” Schroeder told the jury. “It’s a horrific crime of violence and also of greed.”

Schroeder said O’Mahony had previously inherited $1.5 million from the sudden death of her attorney husband in 2017, but spent the money quickly and needed cash at the time of Pedersen’s death.

The prosecutor said Suffolk police detectives became aware of O’Mahony after a friend of Pedersen’s said he was expected to see the Central Islip mother, with whom he’d had a decade-long friendship, on the night he was murdered.

Detectives questioned O’Mahony soon after Pedersen’s body was discovered with a single gunshot wound to the head. She later made several calls to a detective asking if investigators ever found Pedersen’s last will and testament that left her his house in Lynbrook, Schroeder said.

While police had found a will in a location O’Mahony provided, they did not share that information with her, and she later forged a new will leaving her with both of his houses, the prosecutor said. Two witnesses are expected to testify that they fraudulently signed the will.

“Why inherit one house when you can inherit two?” Schroeder said of O’Mahony’s intentions.

Defense attorney Ira Weissman conceded that O’Mahony produced the forged will. He said that does not make her guilty of Pedersen’s death.

“There is no direct evidence as to who actually killed Lee Pedersen,” Mr. Weissman said. “No one who saw him get shot is going to testify in this trial.”

Weissman, who described O’Mahony as a wealthy woman with many assets, said his client and Pedersen, who had no immediate family, were friends who bonded over the loss of loved ones.

Schroeder said prosecutors will rely on the testimony of George Woodworth, 73, of New Jersey, to prove the top charge of second-degree murder. He said Woodworth purchased the gun used in the killing and gave it to O’Mahony, who said she needed it to feel safe at home.

She later told Woodworth she intended to kill Pedersen, Schroeder said, adding that her relationship with both older men was at times sexual and she had a gift for convincing people to do things for her.

The prosecutor said Woodworth let O’Mahony, who he met 15 years earlier in New York City, use his car on the night of the killing as he watched her 5-year-old daughter. He later scattered the gun parts in dumpsters near his New Jersey home, Schroeder said.

A break in the case came during a police search of Woodworth’s house, where investigators located a bag with a spent shell casing and additional bullets. DNA found on the bag matched O’Mahony and Pedersen, Schroeder said.

Weissman said Woodworth’s accusations against O'Mahony came after 10 hours of police questioning and his testimony is in exchange for a four-month prison sentence. He said Woodworth was “obsessed” with O’Mahony and would "do anything for her." 

But Schroeder said it's O’Mahony who had the motive to commit the killing.

“You don’t inherit anything until a person dies,” the prosecutor told the jury. “This defendant decided to speed up the process.”

O’Mahony was arrested at JFK Airport on forgery and grand larceny charges in December 2020. She was indicted for murder the following March, almost one year to the day of Pedersen’s death. At the time of her arrest, O’Mahony had a one-way plane tickets to her native El Salvador for her and her daughter.

By Grant Parpan

grant.parpan@newsday.com@GrantParpan

Grant Parpan covers Suffolk County courts and federal courts for Newsday. A Long Island native, he joined Newsday in 2022.