The Advocate
The Advocate was an alien who had escaped the Time War after Dalek Caan saved Davros, following him through into the normal universe as the Time War was Time Locked. (IDW: Don't Step on the Grass)
The Advocate first met the Doctor when she was at the Shadow Proclamation. She represtented him as his solicitor after they put him on trail for saving Emily Winter]]'s life.
The Advocate then found out that Finch on the Prosacution had set the Doctor up. She tried to sort it out, but was shot by a Judoon, after "Finch" told her to shut up, reducing her to ashes.
She then reappeared in the imposter's cell after he had been found out as a Gizou. He said he was sorry that he failed her, but she said the doctor held the final part of a puzzle and with the Shadow Proclamation believing her dead that she can move through time and space undetected. (IDW: Fugitive)