"The responsibility for that lies with protesters, who took violence into their own hands. But in any campaign, responsibility starts at the top. Any candidate is responsible for the culture of a campaign. And when you have a campaign that disrespects the voters, when you have a campaign that affirmatively encourages violence, when you have a campaign that is facing allegations of physical violence against members of the press, you create an environment that only encourages this sort of nasty discord," Cruz said