After years of snags, work on the electronic surveillance system along the US-Mexico border restarted this week.
Supreme Court limits warrantless police searches to instances when an officer or evidence is in danger.
The Supreme Court must decide whether an Arizona school went too far in strip-searching an eighth-grade girl for drugs.
The US will launch the Kepler spacecraft Friday to look for other Earths.
Conservation land in Mexico and a desalting plant in Arizona are at the center of a debate over the river.