As America's opioid crisis continues to kill hundreds of people each week, many local and state authorities are taking on large corporations to curb opioid prescriptions. Florida recently added Walgreens and CVS to a lawsuit filed last May for the companies' alleged role in the growth of the opioid epidemic. Chris McGreal, author of 'American Overdose: the Opioid Tragedy in Three Acts,' explains how these companies contributed to the scale of the problem in America.