First, how to control mental patients? If family members can't control mental patients, they can be handed over to professional institutions for management. We should establish corresponding institutions to control mental patients. Mental patients are not lonely in society because they are likely to do very dangerous things in the next second. Psychopaths are terrible. They can't control their behavior when they travel. They may beat others at will, or they may hurt others with weapons.
Second, how terrible are mental patients? Most mental patients can't control their emotions well, so they often do something terrible. There are also some mental patients who seem to have nothing to do with ordinary people when they are not sick, but they have made terrible behaviors after they are sick.
Third, summarize. Mental patients should be managed by their families. If mental patients want to go out, then their families should take them out with them and never let them go out alone. After a mentally ill person has done something illegal, his family always refuses to compensate others on the grounds that the other person is mentally ill, but this is also very incorrect.