San Marcos, TX — September 12, 2025, one person was injured in a truck accident at about 2:30 p.m. on the southbound Interstate 35 frontage road.

A preliminary accident report indicates that a 2010 Chevrolet Cobalt crashed into the trailer of a 2004 Freightliner semi-truck that turned out of a private driveway.

A 27-year-old woman who was riding in the Chevrolet was seriously injured in the crash, according to the report. The driver, a 36-year-old man, was listed as possibly injured, while a 2-year-old girl was not hurt.

The truck driver, who was not injured, was cited for making an improper wide turn, the report states.

Authorities have not released any additional information about the Hays County crash at this time.

Commentary by Attorney Michael Grossman

When a passenger car crashes into the side of a turning semi-truck, most people reasonably want to know: Why was the truck there in the first place, and did it turn safely? According to reports, this crash happened when an 18-wheeler turned out of a private driveway and was hit by a car on the I-35 frontage road. Police cited the truck driver for making an improper wide turn, but there’s still a lot we don’t know.

For example, was the trailer already blocking the road when the car came along, or did the truck swing wide into the car’s path mid-turn? That distinction matters. If the truck was stopped across the roadway, that raises serious questions about visibility and timing. On the other hand, if the truck swung out suddenly, that points to driver decision-making or execution of the turn.

Either way, a key part of understanding what happened will involve evidence beyond what can be seen at the scene. Did the truck have an in-cab camera system? What does the dash cam footage show from the car? Does the truck’s engine control module, or “black box,” tell us how fast it was going and how long it had been in motion?

And since the truck was coming out of private property, was it a commercial facility like a warehouse or a yard? If so, was the exit designed to accommodate a safe, lawful turn? I’ve seen cases where drivers were effectively set up to fail because the driveways they used weren’t built for trucks to enter or exit without crossing traffic. In those situations, property owners or facility managers can share in the responsibility for the danger that followed.

We also need to consider how the driver was trained to handle turns like this. Was he following company policy, or cutting corners to save time? In one case I tried, a trucker was trained to use a “buttonhook” method to stay within his lane, but company pressures made him ignore that training to keep on schedule. When that kind of contradiction exists, it can lead to exactly the kind of crash we’re looking at here.

To be clear, we don’t yet know exactly what went wrong in San Marcos. But there’s a big difference between saying “the truck made a wide turn” and knowing why that turn led to a serious injury. Only a full investigation — of video, vehicle data, roadway layout and company practices — will paint the full picture.

Key Takeaways:

• The truck driver was cited for an improper wide turn, but it's unclear whether the turn blocked the road before the car arrived or cut into its path.
• Key evidence includes ECM data, dash cam footage and any in-cab cameras to reconstruct the turn and the car’s response.
• If the truck exited from a commercial driveway, property design and exit visibility may factor into liability.
• Trucking company policies and driver training on how to execute turns safely should be closely examined.
• A complete investigation is essential to determine who’s truly responsible, and why the crash happened.