One year since Luigi Mangione was arrested, items found in his backpack are being discussed in his pretrial proceedings, including a handgun, a silencer, a magazine with bullets wrapped in underwear and a red notebook that an officer called a "manifesto." NBC News' Ellison Barber reports on the latest details from Mangione's pretrial.  For more context and news coverage of the most important stories of our day, click here: nbcnews.com » Subscribe to NBC News: nbcnews.to/SubscribeToNBC » Subscribe to Here's the Scoop podcast: nbcnews.com/heres-the-scoop-daily-podcast Every day, NBC News helps people understand what’s happening and why it matters — through fact-based reporting, meaningful conversations, and powerful stories. From its leading news broadcasts — TODAY, NBC Nightly News, Meet the Press, and Dateline — to NBC News NOW, the 24/7 streaming news channel, plus chart-topping podcasts, the NBC News app, and NBCNews.com, NBC News keeps audiences inf...