A federal judge ruled yesterday that the NSA's collection of phone records and other data most likely violates the constitution.

Judge Richard Leon for the Federal District Court of Washington, DC halted the practice for plaintiffs in the case. The ruling refocuses attention on the balance of privacy and national security and was the first successful legal challenge to the government's surveillance program.

For more, we're joined by Barry Friedman, expert in constitutional law and professor at New York University's School of Law.