CHICAGO (CBS)– The woman who caused a fatal crash on the Indiana Toll Road Labor Day weekend was drunk and on drugs at the time of the incident.

Indiana State Police released toxicology results Wednesday showing Tiara Davis, 25, had marijuana and high levels of alcohol in her system.

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Davis was driving the wrong way down the toll road when she slammed head-on into another SUV in Gary.

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Davis was among four people killed in the crash. A Chicago couple and their 14-year-old son died. The couple’s three other children were seriously hurt.

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