Complex sentence: Another event which attracted much debate was the Supreme Court's annulment of the 1946 conviction of Gregorij Rožman, effectively rehabilitating the Catholic bishop who had been found guilty of war crimes and treason during WWII for his collaboration with the Italian and later German occupation forces.
Split into simpler sentences: Another event which attracted much debate was the Supreme Court's annulment of the 1946 war crimes conviction of Gregorij Rožman. Rožman was a Catholic bishop who had been found guilty of war crimes and treason during World War II as a result of his collaboration with Italian and German occupation forces.