Keith David Palmer was a British police officer who was posthumously awarded the George Medal, the second-highest award for gallantry "not in the face of the enemy". Though unarmed, he stopped Khalid Masood, a knife-wielding terrorist from entering the Palace of Westminster during the 2017 Westminster attack; he was fatally wounded in the attack. He had worked for the Metropolitan Police Service (MPS) for 16 years, and had joined the force's Parliamentary and Diplomatic Protection Group in April 2016.