Both majors are liberal arts and sciences, and the major is investigation. This major cultivates applied senior professionals who have mastered the basic principles of Marxism, good scientific and humanistic qualities, basic police qualities and technical skills, comprehensively mastered the basic theory, knowledge and skills of investigation, and can engage in practical work and teaching and scientific research in domestic public security, criminal investigation, economic crime investigation, technical reconnaissance, drug control and other political and legal departments such as public security organs. The investigation specialty consists of five major directions: criminal investigation, domestic security, economic crime investigation, drug control and technical investigation. This major is a combination of arts and sciences, with a four-year academic system and a bachelor's degree in law. 1, criminal investigation direction. This direction cultivates applied senior professionals who have a solid legal foundation, are familiar with the laws and characteristics of criminal offences under the new situation, master advanced criminal investigation skills, and are competent for criminal investigation practice and teaching and scientific research in this direction. The main courses are: crime scene investigation, criminal case investigation, investigation measures, investigation interrogation, investigation procedures, etc. 2. Domestic security direction. This direction trains applied senior professionals who are familiar with the laws and characteristics of domestic security work under the new situation, master the comprehensive skills of safeguarding national security and social stability, and are competent for domestic security practical work and teaching and scientific research in this direction. The main courses are: domestic security science, engineering reconnaissance, domestic security information science, etc. 3. Direction of economic crime investigation. This direction cultivates applied senior professionals who are familiar with the operating rules of market economy, the laws and characteristics of economic crimes under market economy conditions, master modern economic crime investigation skills, and are competent for the actual work of economic crime investigation and the teaching and scientific research work in this direction. The main courses are: introduction to economic crime investigation, financial crime investigation, tax-related crime investigation, smuggling crime investigation, judicial accounting and so on. 4. Technical reconnaissance direction. This direction trains applied senior professionals with high political quality, strong technical reconnaissance professional skills, strong practical operation ability and competent technical reconnaissance work. The main courses are: introduction to technical reconnaissance, comprehensive case handling of technical reconnaissance and related technical reconnaissance means. 5. Anti-drug direction. This direction is limited to science and engineering candidates. Cultivate applied senior professionals who can engage in anti-drug propaganda, preventive education, anti-drug intelligence, drug case investigation, drug rehabilitation, international cooperation in drug control, control of precursor chemicals and other anti-drug business work in the public security and judicial departments, as well as teaching and scientific research work in their own direction. The main courses are: investigation procedure, general theory of drug control, drug control laws and regulations, drug crime case investigation, drug control information science and so on. This major of public security science trains applied senior public security professionals with good scientific quality, humanistic quality and basic police quality, strong law enforcement ability and social security management level, strong public service consciousness, comprehensive grasp of basic theories and knowledge of law and public security science, and basic skills of public security work to meet the needs of public security work. The major of public security science is composed of public security science and public security legal system, with a four-year academic system and a bachelor's degree in law. 1. Public security direction: This major is a combination of arts and sciences, which mainly trains senior professionals who can engage in decision-making and management practice in public security organs at all levels. The main courses are: introduction to public security, public security case investigation, public security order management, dangerous goods management, public security crisis management, community policing, public security population management, public security prevention and control, public security science and so on. 2. Direction of public security legal system: This direction is limited to candidates of literature and history. It mainly trains senior professionals in public security legal system who meet the needs of public security work and have both ability and political integrity. The main courses are: jurisprudence, Chinese legal history, constitutional law, criminal law, criminal procedure law, administrative law and administrative procedure law, civil law, commercial law, international law, international economic law, police law, criminology, criminal investigation, public security management, etc.