On May 12, 2017, Zhang was suspected committing a crime of infringing trade secrets and subject to criminal detention. Upon acceptance of the engagement, ZhongYin (Hefei) set up a defense team composed of Chen Lei, Jia Kui, You Zhongzheng and other lawyers who had in-depth knowledge about the case and researched on relevant laws, regulations and precedents, and seized every opportunities to submit legal opinions to elaborate that Zhang shall not be held guilty. On June 19, 2017, the people's procuratorate of a district of Maanshan City made a decision on not arresting Zhang and issued an order for guaranteed pending trial. Later, the procuratorate returned the case and requested for supplementary investigations twice.

On April 13, 2018, the public security authority in that district withdrew the case, and the people's procuratorate in that district made a decision on releasing Zhang from the guaranteed pending trial. To this end, the team led by Chen Lei, Jia Kui, and You Zhongzheng successfully defended the client and assisted him to regain freedom by making the case withdrawn.