The so-called re-education, if I may start out, is inherently an extrajudicial procedure. It's an administrative detention determined by public security authorities without the involvement of the courts. There are no court proceedings and also no ways to appeal or to even know what the charge is, and there's no conviction; hence no conviction can be appealed either.
This is the very reason for which the Chinese government itself eventually decided to abolish the nationwide “re-education through labour” system. Local police authorities could easily abuse the system to simply put dissidents or anybody they did not particularly like into a re-education facility.
In Xinjiang we now have rejuvenation of this same system, likely on a larger scale and with greater intensity, and the Uighurs or other Muslims who are interned have no right of appeal. Of course, the issue in Xinjiang is also that even if you were formally censored, even if you were to go through formal proceedings, there is evidence that even so you would have very little recourse to a fair trial. That, however, is a different matter and not the explicit focus of my research.