Question: who is considered the backbone of police services
[{'answer': '26 cantonal police', 'provenance': [{'wikipedia_id': '17910768', 'title': 'Cantonal police', 'start_paragraph_id': 2, 'start_character': 4, 'end_paragraph_id': 2, 'end_character': 22, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '17910768', 'title': 'Cantonal police', 'start_paragraph_id': 2, 'start_character': 0, 'end_paragraph_id': 2, 'end_character': 332, 'bleu_score': 0.9611463610973231, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 15583703571558653264}, 'section': 'Section::::Abstract.'}]}]