Retired probation officer fatally shoots former daughter-in-law, then herself on posh UES street

A retired Chicago probation officer gunned down her former daughter-in-law and then herself along a quiet Upper East Side street Friday morning, as a baby sat in the backseat of a nearby car, police said.

The shocking murder-suicide erupted from a fractious child custody dispute between the shooter, Kathleen Leigh, 65, and victim Marisa Galloway, 45, said NYPD Chief of Detectives Joe Kenny.

The feud could be traced in a long trail of domestic incidents that ultimately led to East 88th Street, just a block from Gracie Mansion, where Leigh twice shot Galloway right after her former daughter-in-law loaded a baby into a parked car about 9 a.m., Kenny said.

Leigh then shot herself, falling onto a sidewalk and dropping a loaded gun between her and Galloway, he said.

“Both had suffered gunshot wounds to the head,” he said.

Galloway’s 1-year-old daughter, who isn’t related to Leigh, was in the backseat of a nearby car but was unharmed in the shooting, Kenny said.

Leigh, a retired Cook County probation officer, moved to the city from Chicago three years ago, Kenny said.

1 woman dead, 1 in critical condition after UES shooting

She is the grandmother of Galloway’s 4-year-old son, he said.

The boy was at the center of a bitter custody battle between Galloway, Leigh and Leigh’s son, Kenny said.

Five domestic incident reports were taken by NYPD cops in the dispute, in addition to two complaints, but no incident had led to an arrest, he said.

The feud appeared to have boiled over Friday morning, as Galloway put her other child — the 1-year-old girl — into a car.

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“She’s then in the process of putting the stroller in the trunk where she is approached by Ms. Leigh who shoots her in the head and then when she’s on the ground shoots her in the back,” Kenny said, describing surveillance footage.

The three gunshots shattered the peace of an otherwise quiet, tree-lined block, a stone’s throw from the official residence of New York City’s mayor.

“I heard yelling, and then I heard shots. I jumped into my doorway for cover,” a witness told The Post as sirens blared around him.

“And then I looked and I saw the lady with the white hair fall onto the sidewalk. I thought something might have happened down by Gracie Mansion and she was hit by a stray bullet,” he continued.

“But then when I went closer, I saw there was another woman lying behind the car who was also shot.”

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Another witness, who gave his name as Mr. Ridriguez, said he pulled up for work just minutes before and heard gunshots. He and others alerted cops at Gracie Mansion about the shooting, he said.

“This is very sad,” he said. “This is a very nice neighborhood, very quiet, the police (are) close by.”

“I never saw anything like this here and I’ve been working here for three years now.”

Cops found Galloway, bloodied but still breathing, slumped near the car’s rear, witnesses and sources said. Leigh lay on a sidewalk, a self-inflicted gunshot wound in her head, Kenny said.

Medics pronounced Leigh dead at the scene, while they rushed Galloway to Weill Cornell Medical Center, where doctors declared her dead on arrival, Kenny said.

Two guns were found near Leigh: a loaded 9-millimeter Glock pistol on the sidewalk near her, and another firearm inside a tote bag she was carrying, Kenny said.

He said cops will investigate whether those are retirement weapons from Leigh’s time as a probation officer.

“Those firearms have no significant history here in New York City,” he said. “They’re not reported as stolen. That’ll be part of our investigation.”

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