Question: when was the law enforcement code of ethics written
[{'answer': '1957', 'provenance': [{'wikipedia_id': '42976239', 'title': 'Criminal justice ethics', 'start_paragraph_id': 24, 'start_character': 397, 'end_paragraph_id': 24, 'end_character': 401, 'bleu_score': 1.0, 'section': 'Section::::In the United States.\n'}]}, {'provenance': [{'wikipedia_id': '42976239', 'title': 'Criminal justice ethics', 'start_paragraph_id': 24, 'start_character': 0, 'end_paragraph_id': 24, 'end_character': 853, 'bleu_score': 0.985238839858627, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 7757025818299172941}, 'section': 'Section::::In the United States.\n'}]}]