Charges have yet to be filed in three recent alcohol-related vehicle accidents, each of which sent people to the hospital with serious injuries.

The three incidents are:

• Kansas University student Colby Liston, 18, had both legs amputated after a vehicle driven by 21-year-old KU student Julian Kuszmaul hit Liston, pinning him between two vehicles in the 1600 block of Tennessee Street on Aug. 26. At the scene, officers suspected Kuszmaul was intoxicated by both marijuana and alcohol.

• Hannah Swank, a 20-year-old KU student, was hit in the road on Ninth Street, near the intersection at Ohio Street, by KU student Jay E. Berryman, 25, on Sept. 2. Both Berryman and Swank were suspected of alcohol intoxication by officers at the scene. Swank was airlifted to a hospital with serious injuries following the accident.

• In the afternoon on Sept. 7, Lawrence man Justin M. Crawford, 39, ran his SUV head-on into a car driven by Jean Drumm, 67, Lawrence, in the 900 block of Maine Street. Both Drumm and Crawford were sent to hospitals after being extricated by emergency crews. Police suspected Crawford, who has at least three prior drunken driving convictions, was intoxicated.

That such cases take weeks, and sometimes months, to lead to arrests and charges isn’t unusual, however, said Douglas County District Attorney Charles Branson, who couldn’t comment on specific cases.

In some cases, police often don’t arrest suspects at the scene, instead opting to wait for official blood test results, which can take several weeks and even months. When the results return, the case is referred to prosecutors, who then must research the criminal history of a suspect, Branson said. That can be a time-consuming process, as prosecutors must obtain certified records from other municipalities. But it’s a necessary process, as the number of previous DUI convictions can lead to different charges, Branson said.

One of the other reasons charges aren’t filed the next day, as is typical in DUI cases, is that there’s a concern suspects could quickly plead guilty and avoid a more serious charge if any victims in the cases later die, which could trigger a manslaughter charge.