A controversial new law in California is at the center of a brutal murder case. A couple was asleep in their bed when they were stabbed to death nearly six years ago. A surprising tip led to the arrest of then 15-year-old Daniel Marsh. He was convicted and sentenced to 52 years to life. Now a new law might set him free when he turns 25. Erin Moriarty joins "CBS This Morning" to preview her report for Saturday's "48 Hours."