CLEVELAND, Ohio -- Four years ago, few seemed to care when Rodney Brown uttered, "I can't breathe" after being tased 11 times by Cleveland police officers during a New Year's Eve traffic stop – at least that's how his family felt. Now the phrase has become a powerful symbol of civil unrest, a rallying cry represented on T-shirts and chanted during marches protesting police use of force cases across the country, like the one involving Eric Garner, who repeated it 11 times while lying face down on a Staten Island sidewalk.