How Luigi Mangione’s notebook helped federal prosecutors build their case and what’s next as he faces mounting charges

It was writings laid bare in a notebook found in Luigi Mangione’s possession, authorities say, that would help investigators build the federal case against him – a well-planned homicide that involved weeks of stalking the movements of his alleged victim, UnitedHealthcare CEO Brian Thompson.

​ It was writings laid bare in a notebook found in Luigi Mangione’s possession, authorities say, that would help investigators build the federal case against him – a well-planned homicide that involved weeks of stalking the movements of his alleged victim, UnitedHealthcare CEO Brian Thompson. Read More Breaking News, Latest News and Videos | CNN