Goone suffered a brain injury. She was updated to stable condition Wednesday.
The judge set bail for Hughes at $500,000, saying the high bail reflected the fact that Hughes reportedly admitted she smoked marijuana the night before the crash. Authorities are awaiting toxicology results that could affect the case. Hughes was not physically injured in the crash.
"I understand the gravity of the situation and the judge's concern, but I was not expecting anything near that when I expressed the fact that the family's resources are very minimal," said Hughes' attorney Jack Levin.
An anonymous donor paid $50,000 of the bond, which is the 10 percent required to release Hughes from jail. The Hughes family said they do not know the donor.
A mother with two teenaged kids from Winnetka called Levin last night.
"She wanted to help this family even though she does not know them and they do not know her. And I've still kept her identity private because that's what she wants," said Levin.
Levin, who said Hughes was ecstatic at hearing she would be released, arrived at the Cook County Jail Wednesday morning with Hughes' passport, which she must turn over, and the $50,000 check from the donor.
After six days in custody, Hughes left the Cook County jail complex in a squad car. A few minutes later she arrived at her Wilmette home and quickly ran inside to see her family, while sheriff's deputies hooked up the electronic home monitor, Hughes' attorney talked about her homecoming.
"She was standing up in her bedroom and I said, 'sort of a silly question, happy to be home?' And she said, 'absolutely, absolutely,'" said Levin.
Levin says Erin then she expressed how grateful she is that Sarah Goone's condition is improving. He says her family is hoping to meet with the Goone family.
"They want to be sure that Sarah's family understands they are very, very concerned about her condition," said Levin.
Hughes' lawyers had expressed concerns early about keeping the teen behind bars.
"I did not want her to be in that population, a young 18-year-old girl from the North Shore. That's a very tough environment to be in," said Levin.
Hughes had been held in custody in the hospital wing of the Cook County Jail.
"The protective measure, precautionary measure, not a privilege but a protective measure, they put her in the hospital unit for 24 to 48 hours," Levin said. "Now, if we had not come up with this bond money thanks to the extraordinary generosity of an individual, they probably could have shifted her to the general population either today or tomorrow."
Hughes will be wearing an electronic monitoring device as she awaits her trial.
The state's attorney said Goone suffered a severe brain injury and had a lot of bleeding to the left side of her brain from a torn artery.
According to her family's web blog, Goone is doing slightly better. A family member wrote Wednesday morning, "She leaned on me, and I said 'I love you.' She said, 'Love you, too.' And I cried. Now she is exhausted from so much activity and is resting, looking forward to a day of discovery and finding out what she is capable of doing. My baby is on her way back."
Goone's mother also writes, "she suffered a hit to the left side of her head that was severe enough to fracture her skull across the front of her forehead. They removed a portion of her skull about the size of her hand on the left side. This will be put back when the swelling subsides."
Hughes' legal problems add to a history of legal issues in her own family. Her mother pleaded guilty last November to possession of marijuana. Her father pleaded guilty in 2008 to felony possession of child pornography and misdemeanor distribution of a controlled substance.
Hughes will be in court on Thursday.