A major change to the murder trial of Tingjun Cao - who has decided to defend himself

He's accused of killing Christchurch real estate agent Yanfei Bao .

The six-week trial is in its third week, and has had a number of disruptions - including Cao accusing a witness of lying.

Justice Lisa Preston says from this point on, he will conduct his own defence, with the opportunity to cross examine all Crown witnesses yet to be called.

His former lawyers have been appointed as standby counsel.