Partey, 32, was granted permission to move to Spain despite being charged with five counts of rape against two women and a charge of sexual assault against a third woman.
The former Arsenal midfielder, who was charged just days after he left the North London club, was granted conditional bail at the start of August in a hearing at Westminster Magistrates’ Court.
Villareal fans have widely criticised the move, booing him throughout their friendly with Villa, but president Roig has defended the move.
He told reporters: "The player is currently undergoing legal proceedings. He maintains his innocence and denies the charges against him.
“The club upholds the presumption of innocence, and it will be the responsibility of the English courts to clarify the facts. We have spent years demonstrating our values with all kinds of activities.
“We respect the presumption of innocence and, of course, condemn any type of violence, whether inside or outside of football. At this moment, Partey is as innocent as the rest of us here. A fundamental right like this must be respected."
Roig then insisted it was the Aston Villa fans that were booing and whistling at Partey, not the Villareal contingent.
He added: "The English (Aston Villa fans) whistled Partey. Not the Villarreal fans. I wouldn’t like our own fans to whistle at players on our team.
“We must stand with the team and respect the presumption of innocence. He is not a convicted player. We must be cautious and wait for justice. Let’s not judge prematurely. Thomas has the right to do his job until there is a conviction."