L. Ron Hubbard was psychiatrically ill, he did evil but it's not clear how far he was responsible for his actions.
Yet, Hubbard was dubbed "schizophrenic and paranoid" by a California Superior Court judge, and Scientology dismissed as "immoral and socially obnoxious" by a High Court judge in London. [1]
Now, decades after Hubbard's death it may be difficult to determine how far Scientology was Hubbard's psychotic delusion and how far Scientology was deliberate fraud. Either way rational people shouldn't take Scientology seriously.