National

A year after the massacre at Sandy Hook Elementary School in Newtown, Conn., gunman Adam Lanza's motives are still unclear. Connecticut Gov. Dannel Malloy says people may just have to be satisfied with what they've known from the beginning — that on Dec. 14, 2012, a horrible thing happened.

The agency is launching a new coordinated research effort to stop citrus greening, a disease imported from Asia that turns fruit bitter and unmarketable. It first turned up in Florida eight years. Now, it threatens to destroy the nation's citrus industry.

The storm's damage and disruption to homes, cities and families is undisputed. But researchers studying the underwater coastline say Long Island fared relatively well. The face of the shore retained much of its shape because underwater ridges of sand just offshore may have cushioned the blow.

Activists from across the country are asking Georgia's governor to support an investigation into the death of Kendrick Johnson, 17, who was discovered dead in a high school gymnasium almost a year ago. State investigators ruled out foul play, but Johnson's parents don't believe it.

Problems persist on the back end of HealthCare.gov, which must process accurate enrollment information so insurers can receive premium payments and start coverage for consumers. Reconciliation of the data just started this week, as time to fix problems is running out.

The historic Colorado floods actually changed the course of some rivers and creeks. That has left many agricultural irrigation ditches and diversion dams useless. Farmers and irrigation companies now find themselves footing the bill to reroute these waterways before spring planting season.

A few determined people are doing their best to keep letters arriving in U.S. mailboxes. One Michigan woman writes up to 60 letters a week — some of them to the students she's met in 50 years of teaching. Some young people are getting into the act, too — including a group at Central Michigan University.

Google and five other tech companies sent a letter to the Senate Judiciary Committee supporting legislation to reform NSA surveillance programs.

The death toll from Sunday's tornado outbreak across the Midwest stands at eight. Many of those who witnessed the devastation say they're shocked that number isn't higher. Early warnings delivered by text message may have helped limit the casualties.

The Los Angeles County supervisor wants to create an independent commission to oversee the department following charges of inmate abuse and racial profiling.