Just before 9:30 p.m. on St. Patrick's Day, Sarah Melissa Steed's car turned sharply to the left and crashed into a ditch on the other side of the road.

The minor wreck left her Toyota disabled in the southbound lane of Maybank Highway on Wadmalaw Island.

During the next seven minutes, cars on the two-lane road pulled out around hers. Some of the motorists stopped and helped. For a few minutes, one of them blocked oncoming traffic with a pickup, its emergency lights flashing.

But by the time Dennis Patrick O'Keefe's southbound car came around a slight bend, the pickup had moved. O'Keefe tried to avoid Steed's car, but his Nissan clipped its back end. Steed's Toyota then slammed into her.

The 29-year-old Hartsville woman was hospitalized with life-threatening injuries, and O'Keefe, 59, was jailed on a misdemeanor drunken driving charge.

The case caught the attention of some legal experts who questioned why O'Keefe hadn't faced a charge of felony driving under the influence. Investigators said then that the more serious count remained a possibility.

But after an investigation unearthed video of the March 17 incident, a Charleston County Sheriff's Office spokesman said this week that the agency likely would not upgrade the charge.

Initial information in a news release from the Sheriff's Office had indicated that Steed was trying to change a blown tire when her car was hit. But the video revealed that she had just been involved in a minor crash.

"We're sticking with the DUI charge," sheriff's Maj. Eric Watson said. "She was on the road looking at the tire. We're not sure if she was about to change it."

The decision is not final because deputies can bring charges later if new evidence surfaces.

Authorities also are looking into whether alcohol played a part in Steed's role in the crash. Steed's attorney, Philip Berlinsky of North Charleston, could not be reached for comment Tuesday or Wednesday.

Steed left Medical University Hospital last week and was expected to recover.

O'Keefe, a resident of Anchor Watch Drive on Wadmalaw Island, had not been arrested before in South Carolina. He was remorseful about what happened, his attorney, Andy Savage of Charleston, said.

Savage said questions remain about whether the lights on Steed's car were activated at the time of the crash. He said his client hadn't seen the car sitting in the road ahead of him until it was too late.

"If someone had been flagging down people to warn them about her accident," Savage said, "maybe it wouldn't have happened."

For a felony DUI charge, authorities would need to prove that O'Keefe was engaged in another unlawful act besides drunken driving when his car hit Steed's.

Deputies figured that his car was going 60 mph in the 55-mph zone, but an estimation so close to the speed limit, Savage argued, wouldn't be enough to prove that he was acting illegally.

Savage instead contended that O'Keefe would have been hard-pressed to avoid the crash, considering the circumstances.

Acquired by Savage, photographs from the scene showed that the front left tire of Steed's car had blown out before O'Keefe came along. It wasn't known if that caused her car to veer into the ditch or if the tire was ruined when the Toyota went off the road.

Surveillance video from the entrance to Long Creek, a gated community across the street, showed Steed getting out and trying to push her car out of the muddy ditch. It had been raining earlier that day.

In the first two cars that came along, drivers saw the passenger side of Steed's coupe blocking their way, and they steered around the Toyota at low speed. The third motorist stopped, and others eventually helped Steed push her car back onto the pavement.

But the vehicle's broadside was still blocking traffic.

Five minutes after Steed went off the road, her headlights were shut off. A pickup that had been blocking oncoming cars relocated to the opposite roadside. It partially shielded the video camera's view of what happened next.

A northbound car moved slowly through the earlier crash site as O'Keefe's southbound sedan approached. O'Keefe was traveling faster than any other vehicle that had appeared on the video.

The footage didn't capture the wreck, but when the pickup moved again to reveal Steed's car, her headlights were again illuminated. The collision had spun the Toyota around.

O'Keefe's Nissan flipped onto its side in the ditch. Its engine compartment was smashed in.

Savage said he had seen no evidence that Steed or any good Samaritans were changing the blown tire at the time, as the Sheriff's Office had told the news media.

In Steed's car, authorities photographed wine bottles of merlot, chardonnay and pink moscato. Empty bottles of strawberry liqueur and a paper bag holding a can of Bud Light Lime-a-Rita also were strewn about.

Whether alcohol played a role in Steed's earlier crash remains part of the investigation, Watson said.

"All of that is part of it," the sheriff's spokesman added. "We're looking at both actions on her part and on O'Keefe's part."

Reach Andrew Knapp at 937-5414 or twitter.com/offlede.