Question: who plays riggs father on lethal weapon tv show
[{'answer': 'Rex Linn', 'provenance': [{'wikipedia_id': '50506293', 'title': 'Lethal Weapon (TV series)', 'start_paragraph_id': 31, 'start_character': 12, 'end_paragraph_id': 31, 'end_character': 20, 'bleu_score': 1.0, 'section': 'Section::::Cast and characters.:Recurring.\n'}]}]