UPDATED 12/16/11 11:07 a.m.

CHICAGO (CBS) — The family of a woman killed on the Eisenhower Expressway shortly after her release on drunken driving charges says she should never have been left alone.

As CBS 2’s Susanna Song reports, Diana Paz, 25, was struck and killed by a car as she walked onto the expressway in the wee hours Sept. 2.

LISTEN: WBBM Newsradio’s Nancy Harty reports

Just minutes earlier, Illinois State Police had dropped her off at a nearby gas station. She had bonded out after being arrested for drunken driving as she drove home from her own birthday party, and state police gave her a ride to the west suburban gas station after she told them had no family or means of getting home.

Now, Paz’s family says she was still drunk at the time she was dropped off, and never should have been left alone. Their attorney, Timothy Cavanagh, on Tuesday morning said the Cook County Medical Examiner’s Office found that Paz’s blood alcohol level was at least twice the legal limit.

“She was twice the legal limit or beyond, depending on which test, and I think what it tells us is the State Police I-bonded a young girl out who was 25 years old, in the dead of night, with no cell phone, no wallet, no purse, no money, no way to contact family, and dropped her off at a gas station next to the highway, which I don’t think is responsible,” Cavanaugh said.

The information about Paz’s blood alcohol level is contrary to what state police told the media immediately after the deadly accident, Cavanaugh said.

Paz’s family members also say they are having a hard time getting information from state police. Cavanagh, who is suing state police on the family’s behalf says he filed an emergency motion to get all the information about the events that led to Paz’s death — including all medical records and video at the BP gas station where Paz was dropped off.

But Cavanagh claims despite a judge’s order, state police have not complied.

Paz was pulled over at 3:23 a.m. on Sept. 2 for driving the wrong direction on the Eisenhower. She failed a field sobriety test and refused a breathalyzer.

Paz was arrested and processed at the police station in Westchester. She was released after signing an I-bond at 5:40 a.m. the same day.

Paz asked police to take her to the nearby BP gas station. Moments later, she was walking in a marked median area on the Eisenhower Expressway just east of Westchester Boulevard. That was when she was hit by a truck driver and killed.

Paz had hoped to finish school and pursue a career in criminal justice, her sister said. She left behind a 5-year-old son, Erik, her family says.

Diana Paz’s sister, Maria Paz, says her parents are taking care of Erik now.

“He talks about her all the time, and he misses her so much,” Maria Paz said.

State Police said in September that Paz was alert and coherent at the time of her release. State police are not required to transport motorists, but as a courtesy, officers will transport stranded motorists within a reasonable distance. There’s no policy requiring Illinois state police to do this.

On Friday, state police said they were in the middle of investigating and could not comment on the probe.

But state police spokeswoman Monique Bond says Paz police cannot hold people against their will if the I-bond themselves out.

The Sun-Times Media Wire contributed to this report.

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