Legal analysis: the standard of judicial expertise: 1. Psychiatry refers to a serious psychological disorder, and patients' cognitive, emotional, will, behavioral and other psychological activities can appear persistent and obvious abnormalities;

2, unable to study, work and live normally;

3. The actions and behaviors are difficult to be understood by ordinary people, which makes them look strange and different.

4. Under the control of morbid psychology, he commits suicide or attacks or hurts others;

5. Patients have different degrees of self-control. Patients often lose their judgment on their mental symptoms, think that their psychology and behavior are normal, and refuse treatment.

methods of judicial expertise: 1. out-patient expertise; 2. out-patient expertise; 3. in-patient expertise; 4. absence expertise

legal basis: criminal procedure law of the people's Republic of China

article 146 when it is necessary to solve some specialized problems in a case in order to find out the case, people with specialized knowledge should be appointed and hired for expertise.

article 147 after conducting an appraisal, an appraiser shall write an appraisal opinion and sign it. If an appraiser intentionally makes a false appraisal, he shall bear legal responsibility.

article 148 the investigation organ shall inform the criminal suspect and the victim of the expert opinions used as evidence. If a criminal suspect or victim applies, he may make supplementary appraisal or re-appraisal.