Complex sentence: The second trial was the subject of a television documentary "The Murder Trial", which was shown on Channel 4 on 9 July 2013, only the second time that footage from a British murder trial was broadcast on television.
Split into simpler sentences: The second trial was the subject of a television documentary "The Murder Trial", which was shown on Channel 4 on 9 July 2013. This was only the second time that footage from a British murder trial was broadcast on television.