Bland's sister: Investigators' credibility on shaky ground

Sharon Cooper, the sister of Sandra Bland, speaks to CNN's <a href="http://www.cnn.com/profiles/don-lemon-profile" target="_blank">Don Lemon</a> following the release of <a href="http://www.cnn.com/2019/05/07/us/sandra-bland-cell-phone-video/index.html" target="_blank">new video from Bland's vantage point during the 2015 traffic stop</a> that led to her arrest.