Symptom:
When a down interface is configured on Catalyst switch 3850 for a fixed speed and duplex value, the "show int status" command shows the correct speed, but it shows duplex as auto.

This behavior is seen only on an unconnected port.

Example:
#######

CAT3850#show run interface gigabitEthernet 1/0/2
Building configuration...

Current configuration : 62 bytes
!
interface GigabitEthernet1/0/2
 speed 100
 duplex full
end

CAT3850#show interfaces status | include Gi1/0/2 
Gi1/0/2                      notconnect   1            auto    100 10/100/1000BaseTX

Conditions:
The problem is seen on down interface, but when the link is ?up?, it shows the correct settings.