An Army officer who led a sexual abuse prevention program at Fort Hood has pleaded guilty to several charges stemming from a prostitution ring at the sprawling base in Central Texas.

Sgt. 1st Class Gregory McQueen pleaded guilty to 15 counts as his court-martial began Wednesday, including charges of pandering and conspiracy to solicit prostitution. However, he pleaded not guilty to sexual assault.

Two soldiers testified last year that McQueen recruited them and other cash-strapped female soldiers to join the prostitution ring. One woman testified that McQueen arranged for her to have sex for $100 with another soldier, Master Sgt. Brad Grimes.

Grimes has already been demoted and reprimanded. McQueen was charged in March 2014.