Question: when did law and order special victims unit start
[{'answer': 'September 20 , 1999', 'provenance': [{'wikipedia_id': '197060', 'title': 'Law & Order: Special Victims Unit', 'start_paragraph_id': 46, 'start_character': 57, 'end_paragraph_id': 46, 'end_character': 76, 'bleu_score': 1.0, 'section': 'Section::::Reception.:U.S. television ratings.\n'}]}]