The young woman known as "La Diablita," the Little Devil, is on trial in Suffolk County.
Prosecutors say Leniz Escobar helped orchestrate the 2017 massacre as a teenage associate of the gang before falsely claiming to be a victim in the ambush.
Escobar has pleaded not guilty to racketeering charges in the four deaths that prosecutors described as "a horrific frenzy of violence" involving machetes, knives and tree limbs in a Central Islip park.
MS-13 had been seeking to settle a score, prosecutors allege, and believed the young victims to be members of the rival 18th Street Gang. The victims' families have denied that any of the slain men were in a gang.
Prosecutors allege that Escobar, who was 17 at the time, was seeking to curry favor with MS-13 and alerted its members to the victims' location in a wooden area in Central Islip. Under MS-13 rules, the killings had been "pre-authorized" by gang leadership, prosecutors said, and contributors to the carnage stood to gain membership or ascend the organization's ranks.
Authorities said Escobar later tossed her cellphone from a moving vehicle - as well as a SIM card that had been removed and damaged so badly law enforcement couldn't recover its contents.
One of the first witnesses, who was 15 at the time, testified last month that Escobar was responsible for picking the spot in the woods and showed the boys how to get there. He said they were there smoking pot when a group of seven to nine men came through a fence very deep in the woods with machetes and sweatshirts covering their faces.
He said they told the group of five boys to get down on their knees and to not move or they would all be killed.
The witness testified that he got up from his knees, jumped on top of a fallen tree and then over a fence to get away.
After he got over the fence, he said there were two men waiting there who chased after him, but he was able to get away.
The boy then went to police and moved from Long Island to another state a few days later.
Prosecutors released a phone call that she had with her boyfriend the day after the murders from inside jail, and she mentioned someone who 'missed the train'. That was most likely the one man who was able to run away and survive this brutal attack.
Amador: Why do you say that you're not so good.
Escobar: Because the person that missed the train spilled the beans, and I, well...
Amador: What? Uh-huh. What happened?
Escobar: The person that missed the train spilled the beans.
Amador: So...the one that missed the train, and the others didn't. I already know that.
Escobar: Right, but he spilled the beans with the cops.
In that same call, Escobar told her boyfriend that she and her friend Keyli Gomez who is also accused of luring these men into the woods, she has been cooperating with prosecutors on this trial.
On that recorded line, Escobar tells her boyfriend that she and Gomez had been practicing all morning long, rehearsing their story for police.
Escobar's attorney says that she made these comments to her boyfriend because she was scared of the MS-13 gang and she wanted to pretend that she was okay with this entire thing.
The defense contends that Escobar had no knowledge that the boys would be murdered that night and that she didn't even know the men responsible.
MS-13, also known as La Mara Salvatrucha, recruits young teenagers from El Salvador and Honduras, though many gang members were born in the U.S.
The gang has been blamed for dozens of killings since January 2016 across a wide swath of Long Island.
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