Valium 10 is a hefty dose. Usually used at that dosage for sedation or extreme muscle spasms.
Valium hits the same brain receptors as alcohol. That is why it is used for detox. It is a major muscle relaxant, and anxiety reducer.
Been around since the fifties and I would guess this is not why this man caused over 500 causalities.
Your information is better than mine. I’m not a drug taker so I really should have looked it up.