A military jury cleared an Army sergeant Friday of all charges that he abused a detainee at a U.S. detention facility in Afghanistan (search).

Sgt. Duane M. Grubb (search), from the Cincinnati-based 377th Military Police Company, is the third soldier from this company to be acquitted on charges of striking and otherwise abusing detainees in Bagram (search), Afghanistan.

The all-male jury of four officers and four enlisted men deliberated for about a half-hour. Grubb and another soldier were accused of striking Zarif Khan (search), an inmate whose behavior earned him the nickname "Timmy," after a mentally slow character on the cartoon "South Park". (search)

Prosecutor Capt. John B. Parker urged the jury to remember that the case was about standards, and that Grubbs is accused of violating those standards.

"The bottom line is that the Army standard is not ambiguous about how you treat people." He asked the jury to send a message that these actions are not those of respected members of the Army and the military police corps.

Grubb's lawyer, Capt. Robert Fellrath, said the testimony by the government's sole eyewitness, former Spc. Jeremy Callaway, contradicted his own testimony in other cases.

He also asked the jury to ponder why Callaway was the only person to see the abuse when other soldiers would have been in the area when the alleged attack occurred.