The Original Purpose of LSD
When LSD was first invented, the CIA took a huge interest in it as a potential psychological weapon and as a truth serum. Initial animal experiments on cats showed they began to hallucinate and grow fearful of mice.
The CIA believed that they could potentially use it as a weapon of war. Paranoia climbed in the CIA’s ranks after hearing rumors and reports of “brainwashed” G.I.’s returning from Asia, post-war. Worrying they were falling behind in war tech, they did what they could to make new weapons.
You can’t release a weapon in battle without knowing what it does. So, they did human experimentation on jail inmates and other marginalized civilians.