Legal analysis: lawyers do not have the power to check the phone chat records, unless the parties agree. Cell phone chat records belong to personal privacy, even if the court is not this view authority. Freedom and privacy of communication are protected by law, unless it is related to national security or the need to track down criminal offenses, and even in this case, only the state power organs, such as public security, procuratorate, the judicial system and other units can query. So when you encounter such a request, you can explicitly refuse it.
Legal basis: The Constitution of the People's Republic of China Article 40 The freedom and privacy of communication of citizens of the People's Republic of China shall be protected by law. No organization or individual may, on any grounds whatsoever, infringe upon the freedom and privacy of communication of citizens, except that the public security organs or procuratorial organs shall inspect communication in accordance with the procedures prescribed by law in the interests of national security or the pursuit of criminal offences.