A Spanish judge moved closer on Tuesday to investigating former Bush administration officials over torture at Guantanamo Bay, raising the possibility that two Spanish probes could focus on activities at the U.S. base.

In a ruling, Judge Eloy Velasco asked U.S. authorities to confirm if an investigation already exists in the United States into accusations of complicity with torture against six men including former U.S. Attorney General Alberto Gonzales.

The request is a formality because it is public knowledge that Gonzales and the other men face no judicial probe in their home country. But it is necessary so Judge Velasco can argue that he can open an investigation.

Another Spanish judge, Baltasar Garzon, has launched a separate criminal probe into accusations of torture at Guantanamo, which U.S. President Barack Obama has promised to close.