Courtesy Aimee Cagle(NEW YORK) --  A judge in Michigan has ruled that four teens who pleaded guilty to manslaughter in the 2017 highway rock-throwing incident that led to the death of Kenneth White will be sentenced as adults.

In July 2018, when the teens' lawyers entered pleas for Mark Sekelsky, Alexander Miller, Trevor Gray and McKayden Payne, they'd included a proposal for juvenile sentencing.

Genesee County Circuit Court Judge Joseph Farah rejected that request during Tuesday's hearing. Instead, he gave the teens and their lawyers until Aug. 20 to accept being sentenced as adults, reject his revision to the plea agreement and try to negotiate a new one or head to trial. The teens could choose their options as a group or individuals.

Farah rejected the advice of every professional juvenile expert who testified at the sentencing hearing in the fall, all of whom had recommended juvenile sentencing. In court Tuesday, he said that while none of the four teens had dropped the fatal rock, Farah repeatedly said that not one had been forced or cajoled to be there.

"The seriousness of the alleged offense is as high as it gets," he said in the court Tuesday. "This is a homicide."

Theresa Simpson, White's mother, said on Tuesday after the hearing that she was pleased with the judge's decision.

"I'm so glad that Kenneth is getting the justice he deserves. ... My prayers were answered," Simpson told ABC News affiliate WXYZ-TV in Detroit. "I'm ecstatic over the decision that was made today. ... It's what we all wanted for him."

On Oct. 18, 2017, at about 8:30 p.m., White and his friend Steve Amthor were driving home from work, heading south on I-75 at about 70 mph in a van. Amthor said he saw a large rock coming toward the vehicle, in which White was the passenger, authorities told ABC News.

The rock, according to Amthor, entered the passenger side through the windshield, hitting White, 32, in the face and then ricocheted from his face to his chest, authorities said. About 20 rocks were found strewn on the highway, police said.

In court Tuesday, Farah referred to two days of exchanged SnapChat messages among the teens in which "the letters 'LOL,' 'LMAO' or 'HAHA' appear ... and many after it was learned that they had killed somebody."

"We could possibly go to prison for life from this," Farah read from the messages in court. "You guys knew what could've happened. And, if we do get caught -- which we won't -- it's our own fault. LOL. We gotta take our punishment. Lay low for a while and everything will be fine."

Farah said that after it was reported in the news that White had died, the conversation between the teens on SnapChat then turned to getting teardrop tattoos to commemorate the crying of White's family.

"Well, maybe, we should (get) tattoos with 'Crip Gang' next to the tattoo," the judge read.

Farah said the rock that killed White was not the only item tossed from the overpass by the teens. He said that tire irons, mufflers and even a shopping cart had been thrown as well though at different times and at different locations.

"What was the purpose? Wait till the road cleared and drop to see it break? No. (It was) to make contact in this (game) called 'Overpassing.' To be able to say aloud 'Dinger!' when a car was hit," he said.

A fifth suspect -- Kyle Anger who was 18 at the time -- is the one accused of throwing the actual rock that killed White. He pleaded guilty to second-degree murder in exchange for other charges being dropped. He is scheduled to be sentenced at a later date.

All five teens had been originally charged as adults with second-degree murder, conspiracy to commit second-degree murder, six felony counts of malicious destruction of property and two misdemeanor counts of malicious destruction of property.

Lawyers for the teens said they were disappointed with the judge's ruling.

"We're back to the drawing board. Each one of the four boys has a mechanism within that plea that they have the option to withdraw the plea should the court not have granted juvenile sentencing. So the court made its decision, not granting juvenile sentencing, and I'm sure all the lawyers are gonna go back to the drawing board," said lawyer Michael Manley.

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