As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
THE NR 1 ENGINE THRUST REVERSER UNLOCK LIGHT ILLUMINATED. CAPTAIN FELT THE AIRCRAFT YAW, SO HE SHUT DOWN THE NR 1 ENGINE. FLIGHT RETURNED TO FIELD AT CLT AND LANDED WITHOUT FURTHER INCIDENT. AN EMERGENCY WAS DECLARED. TOTAL SINGLE ENGINE TIME WAS 20 MINUTES. MAINTENANCE FOUND THE NR1 ENGINE THRUST REVERSER STOWED WHEN THE AIRCRAFT ARRIVED AT THE GATE. DETERMINATION WAS MADE TO BE AN INDICATION PROBLEM. THE AIRCRAFT WAS RELEASED ON MEL. MAINTENANCE ACTION PENDING.