Question: what is the function of the secret service
[{'answer': 'conducting criminal investigations', 'provenance': [{'wikipedia_id': '58221', 'title': 'United States Secret Service', 'start_paragraph_id': 1, 'start_character': 154, 'end_paragraph_id': 1, 'end_character': 188, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'answer': "protecting the nation 's leaders", 'provenance': [{'wikipedia_id': '58221', 'title': 'United States Secret Service', 'start_paragraph_id': 3, 'start_character': 102, 'end_paragraph_id': 3, 'end_character': 137, 'bleu_score': 1.0, 'section': 'Section::::Primary missions.\n'}]}, {'provenance': [{'wikipedia_id': '58221', 'title': 'United States Secret Service', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 416, 'bleu_score': 0.822181541002111, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 13318587686179974909}, 'section': 'Section::::Abstract.'}]}]