Jim Watson / AFP - Getty Images file

Pfc.Bradley Manning is escorted by military police as he departs the courtroom at Fort Meade, Maryland on April 25, 2012.

A military judge denied a motion to dismiss charges against Army Pfc. Bradley Manning, who is accused of providing reams of classified documents to WikiLeaks, but agreed that Manning should have a 112-day reduction from his sentence, if convicted, due to mistreatment during confinement.

Col. Denise Lind, who made the announcement during a four-day pretrial hearing that started Tuesday at Fort Meade, Md., said that Manning's confinement at a military jail in Quantico, Va., was "more rigorous than necessary," and "became excessive in relation to legitimate government interests."

Even so, Lind said dismissal of charges is "not appropriate," and would make sense only in the case of "outrageous" conduct on behalf of Manning's jailers.

Manning faces 22 charges, including aiding the enemy, which carries a maximum of life behind bars.

His defense attorney David Coombs argued that the military held the 25-year-old intelligence analyst in unduly punishing pretrial conditions for nine months after his 2010 arrest.

A 28-page motion filed in August said Manning was locked up alone in a small cell for nearly nine months at Quantico and forced to sleep naked for several nights — treatment his lawyers say constituted illegal punishment.

The document said Quantico officials operated in a culture where "anything goes" and "nobody is held to account for their conduct," willfully ignoring the advice of medical professionals who did not support the solitary confinement.

Jailers at the Marine Corps brig in Quantico testified that they considered Manning a suicide risk and that they were only trying to keep him from hurting himself and others by keeping him in a windowless, 6-by-8-foot cell for 23 hours a day.

In December, prosecutors conceded that Manning was improperly held on suicide watch for seven days and recommended he get seven days' credit at sentencing.

Bradley Manning heads to court to argue against trial in Wikileaks case

Manning has been held in pre-trial detention since May 29, 2010.

The judge's rejection of the motion to throw out the charges had been expected by legal observers.

Do motives matter?
This week's pretrial hearing includes arguments on whether Manning's motivation matters.

Prosecutors want the judge to bar the defense from producing evidence at Manning's March 6 trial regarding his motive for allegedly leaking hundreds of thousands of secret war logs and diplomatic cables. They say motive is irrelevant to whether he leaked intelligence, knowing it could be seen by al-Qaeda.

Manning allegedly told an online confidant-turned-informant that he leaked the material because "I want people to see the truth" and "information should be free."

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Attorney Coombs said Tuesday that barring such evidence would cripple the defense's ability to argue that Manning leaked only information that he believed could not hurt the United States or help a hostile power.

Manning has offered to take responsibility for the leaks in a pending plea offer but he still could face trial on charges that include aiding the enemy.

The Associated Press and NBC News' Kari Huus contributed to this report.

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