Contractor Accidently News Today

state university as police are still trying to piece together the gunmans motive. this hour, ill ask the michigan attorney general about the many unanswered questions in this investigation. also today, former vice president mike pence is speaking out for the first time about his plans to fight a new subpoena from the u.s. justice department. hes arguing that his effort to avoid testifying in the special counsel probe of donald trump is about the separation of powers. republican nik...

>> thank you, madame chair, for the question. >> reporter: one focus, the system that failed last month, triggering the first ground stop since 9/11. the cause, a contractor accidently deleting files during system maintenance. >> that no longer have access to the facilities. >> reporter: the faa is moving to a more modernized system by 2025, and is putting safeguards in to prevent a repeat. >> were about halfway through it. >> is there a redundancy being built into it, or can a single screw up g...