Every year, thousands of migrants cross the border from Mexico to Arizona, leaving behind artifacts from their journeys. Some of the items end up in trash bags, others in a museum. Still others end up in the morgue.

As the Supreme Court heard arguments this week on sentencing juveniles, more than a dozen families of teenagers sentenced to life without parole came to Washington to advocate hand-in-hand with the families of the people their children murdered.

The four things to watch for in Louisiana are Romney's share of the vote which must be 25 percent or more for him to gain any of the delegates who are in play Saturday. Also if he gets a large enough share of Catholic and evangelical votes, that could help him get to 25 percent as well.

Saturday is presidential primary day in Louisiana where 20 delegates are at stake. Mitt Romney, Rick Santorum, Newt Gingrich and Ron Paul all campaigned there Friday. Romney leads in national polling, but Santorum is ahead in Louisiana.

Murder charges have been filed against Staff Sgt. Robert Bales, accused of killing 17 Afghan civilians. Now, an investigative officer will decide whether there's enough evidence to go forward with a court martial, leaving a number of legal challenges ahead for the prosecution and for the defense.

After John McCain so quickly clinched the Republican presidential nomination the last time around, the party changed its rules with an eye to extending their primary season, reaping public interest for months like the Democratic primaries of 2008. Host Scott Simon talks with GOP strategist Mike Murphy about whether this extension has been a help or a hindrance.

Outrage over the death of unarmed teenager Trayvon Martin in Sanford, Fla., has spread. Thousands protested this week calling for the arrest of George Zimmerman, the neighborhood watch volunteer who says he shot Trayvon in self-defense. NPR's Joel Rose tells host Scott Simon the latest.

This week Mitt Romney and Rick Santorum got their Secret Service code names: Romney is "Javelin," Santorum is "Petrus." Presidents have been getting code names back to Harry Truman, who was called "General." Ian Chillag and Mike Danforth of the podcast How To Do Everything look into how these code names are assigned.