There is no bail in the military justice system so pretrial detention for serious crimes is not out of the ordinary, and since when the investigation started there was every possibility that the defendants would be charged with a capital crime the detention was certainly warranted. Even in the civilian justice system bail can be denied in serious cases.
You are unaware of the details.
They were held in solitary confinement in conex boxes in the Iraqi heat for 3 weeks until 3 of them signed a confession.
Once released, those 3 recanted.
They were flown back to the US and it was only then that they were able to phone their families and tell them they were in jail.
I guarded the brig once on ship, the red Cross informed the families of those guys, but not the Pendleton 8.
Also, to a man, NOW, the 8 all hold to their story. NOW that they arent being held in hot boxes with little food, water, and head calls, being sleep deprived and interrogated round the clock until 3 of them cracked.