Adam, James thank you for your responses! This sentence is about Nikolay Brukhansky, a Russian psychiatrist and one of the founders of the Soviet forensic psychiatry. He was sent into exile for the suggestion to exempt psychopathic persons from criminal responsibility. He died there in 1948.

This looks good as it is. There are different ways to write the same sentence but I wouldn't call any of them "better." Who is he? It sounds like an interesting subject.

Mariam, this sounds natural and clear as it is. An alternative is: After his suggestion at the 1936 II Congress of Psychiatrists and Neuropathologists to exempt psychopathic persons from criminal responsibility, he was accused of counter-revolutionary activity, even despite his outstanding achievements in the Soviet study of forensic psychiatry. I think both work. The option connects his action (suggestion) and the response (accusation) together. It depends on the preceding and trailing sentences. In some ways I would err towards the way I suggest, but this gets down to context and personal choice of expression and writing style. This way, the "Despite outstanding...." clause is placed in a trailing position of secondary contribution to the main point of the sentence. This sounds like a very interesting subject!