When a client is accused of participating in a hacker group, the defense strategy can focus on the following aspects to explain that its actions are intended to improve the level of cybersecurity education: 1. **Legitimate Intent**: Emphasize that the client's original intention of participating in the hacker group was to reveal and educate others about potential threats to cybersecurity, rather than to maliciously attack or obtain illegal benefits. 2. **Good Faith Disclosure**: If the client has participated in the process of revealing vulnerabilities, especially through the Responsible Disclosure program, explain that it is intended to help companies and society fix vulnerabilities rather than exploit them. 3. **Education and Training**: Point out how the client promotes cybersecurity knowledge among the public or specific groups through speeches, publications, training courses or workshops, and contributes to the overall improvement of the cybersecurity level of society. 4. **Cooperation and Advocacy**: Mention whether the client has cooperated with the cybersecurity community, enterprises or governments to participate in the formulation of cybersecurity policies, standardization work or advocate for higher security awareness. 5. **Harmless Testing**: Defend that the client's actions were harmless tests conducted in a controlled environment, with the purpose of demonstration and education, rather than causing substantial harm. 6. **Case Context**: Provide specific examples showing situations where the client helped identify and resolve serious security vulnerabilities, which benefited public safety. 7. **Change and Repentance**: If relevant, emphasize that the client has recognized the problem and is actively engaging in legitimate cybersecurity work and helping others improve their security skills. The above strategies, combined with specific examples and evidence, can effectively demonstrate the positive aspects of the client's behavior and its contribution to cybersecurity education.