"The department attempts to justify the mass separation of every single child from the YFZ Ranch from his or her mother on the ground of 'systematic and institutionalized sexual abuse of children.' That is a very strong allegation, yet it is not supported by sufficient evidence," attorneys for TRLA write.

"It is not reasonable to assume that all members are of one mind regarding their beliefs."

Texas RioGrande Legal Aid's original petition also argued that an April 17-18 adversary hearing for the children was improperly held "en masse" instead of holding hearings for each individual child. But DFPS says the actions of the parents forced the judge to hold the single hearing.

"It is the department's contention that (the mothers), by their conspiracy of silence, purposefully confused the identity of the children, which forced Judge Walther to conduct the proceedings as she did."

DFPS also says the FLDS women have no legal standing to have the judge reverse her ruling because they have "repeatedly declined" to even identify their children and the fathers. Neither the court nor the child welfare agency should "be forced to play guessing games when the safety and well-being of these children are at stake," the documents state.

Attorneys for the mothers denied the allegation but filed a list Friday of the names of the children of their clients.

The Department of Family and Protective Services also argued that all the mothers had an opportunity, through their attorneys, to confront and cross-examine the witnesses during the April 17-18 hearing. To hold individual hearings would have taken weeks or even months and would have been an "extraordinary waste of judicial resources."

In removing the children, attorneys for the mothers say the judge failed to consider less restrictive options such as ordering the men ("the alleged perpetrators of abuse") to leave the ranch or ordering mothers and their children to live elsewhere during the investigation.

DFPS argues that if the state does not have physical custody of the children, what's to prevent the mothers from leaving the state with them? It also asks how the court could know for certain which child legally belongs to whom.

As "the largest child protection case documented in the history of the United States," the department said the sheer numbers of FLDS children prevented it from pursuing other options it might have considered in a more typical case.

As for possible temporary restraining orders against men at the ranch, DFPS says that wasn't practical. "How could the department have identified the alleged perpetrator or perpetrators when the evidence demonstrated that the entire male and female population at the YFZ Ranch had been enculturated into the belief that underage marriage was sacrosanct?"