Question: what actor played ben stone on law and order
[{'answer': 'Michael Moriarty', 'provenance': [{'wikipedia_id': '916718', 'title': 'Michael Moriarty', 'start_paragraph_id': 0, 'start_character': 0, 'end_paragraph_id': 0, 'end_character': 16, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '916718', 'title': 'Michael Moriarty', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 682, 'bleu_score': 0.778898484721937, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 9958453064952463999}, 'section': 'Section::::Abstract.'}]}]