Depression is a psychological abnormality, but its nervous system is normal, and patients can correctly and completely identify and control their own behaviors. People with depression kill people, usually on purpose. Of course, the possibility of death caused by negligence is not ruled out! Those who use their depression to try to escape legal sanctions and commit crimes should not only bear criminal responsibility, but I think we should consider giving them heavier punishment!
Of course, criminal responsibility depends on the patient's age.