Rana made the plea before US District Judge Matthew Kennelly in a Chicago court on Wednesday, Jan 6.
Rana contended that because he deserted the military and isn't welcome back in Pakistan, he's not a flight risk and should be released on bond.
A motion filed by Rana's lawyers also provided new details about his background-including Rana's admitted desertion from the Pakistani army.
"Defendant's Pakistani background should raise no concerns whatsoever regarding risk of flight," the motion said.
It also said that, "Serving as a physician in the Pakistani military Rana suffered from two high altitude conditions as he was transported to high elevation without proper acclimatisation."
However, Federal prosecutors say he should remain behind bars because he knew about plans to commit terrorist attacks on Mumbai in 2008 that resulted in 166 deaths.