The Missouri Supreme Court has upheld the conviction of a southwest Missouri man who told police he had considered committing a mass shooting at a Wal-Mart or a movie theater.

The court ruled Tuesday that Blaec Lammers' statements were sufficient to uphold his attempted first-degree assault and armed criminal action convictions.

A detective interviewed Lammers after his mother warned police he had bought two assault rifles and she was worried he wasn't taking his depression medicine.

Lammers told police he had thought about shooting up a Wal-Mart after watching a movie about the Columbine High School shootings, but changed his mind because he didn't want to go to prison.

The court held that Lammers' gun purchases and his shooting practice constituted sufficient steps toward committing the shooting.

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