The issue focused on the government's tax policy, with public concern about high levels of tax avoidance.

A law enforcement official said that after his court appearance in late June, Mr. Law had been given a legal travel document to leave China. The official spoke on condition of anonymity because he was not authorized to discuss the case.

But it is unclear if he has left China. A Chinese foreign ministry official who asked not to be named said in an interview on Monday that he could not comment on any