Pat down search articulation causes reversal

In Gatlinburg an officer responded to a disturbance. He decided for his own safety to pat down the agitated gentleman who was arguing with a female, who had called the police. The Court decision reversed the conviction. It appears that the problem may have been more of a lack or articulation than an improper decision to pat someone down. What officer in this setting would not feel the need to pat someone down in this situation. Read the case at:
http://www.tsc.state.tn.us/sites/default/files/state_of_tennessee_v_samir_ramon_mejia.pdf