Complex sentence: While Bratton, who introduced stop-and-frisk under Giuliani, promised it would be used "legally, respectfully," and less frequently, some de Blasio supporters were disappointed with Bratton's appointment.
Split into simpler sentences: While Bratton, who introduced stop-and-frisk under Giuliani, promised it would be used "legally, respectfully," and less frequently. Some de Blasio supporters were disappointed with Bratton's appointment.