Female soldiers at Fort Hood testified Monday that they were recruited for a prostitution ring set up by a sergeant involved in the sexual assault and harassment program at the Central Texas post.

The testimony came as the court-martial began for another Fort Hood soldier accused of using the service, which Army prosecutors said preyed upon young, cash-strapped female soldiers at Fort Hood.

Master Sergeant Brad Grimes is a 17-year Army veteran who served in Iraq and Afghanistan. Army prosecutors said in the military court on Monday that Grimes participated in the prostitution ring set up by another Fort Hood sergeant not yet charged but still under Army investigation, the Austin American-Statesman reported.

The case arose from an investigation of a lower-level coordinator of Fort Hood's sexual assault and harassment prevention program. The Army said a noncommissioned officer involved in the program recruited female soldiers for the prostitution ring.

Defense attorney Daniel Conway said Grimes is being court-martialed because he refused a deal to testify against the other soldier. Grimes denied the charges of adultery and conspiring to pay for sex from a Fort Hood private.

"At the end of the day, Master Sgt Grimes chose to do the right thing and not have sex with that young lady," Conway said. "This is really a case about sex parties, and Master Sgt Grimes had nothing to do with that."

Conway asked Col Gregory Gross, the military judge presiding over the trial, to throw out the case against Grimes. He argued that the Army high command and top federal officials, including President Obama, had biased the process by pressing for prosecutions over military sexual assault allegations. Gross declined to dismiss the case.

The trial is to continue Tuesday.