After R2 escaped the heavy hand of justice due to a mistrial at the end of episode I, the Galactic Attorney and his prosecutors are convinced that it was C3PO who tampered with their evidence files leading to the judge's verdict. After some sniffing around the seedy underbelly of the internets they learn that theirs are not the only protocols that have been "violated" by the seemingly anxious and bumbling droid. Designer neurodrugs, allegations of impropriety from droids of all walks of life (starship AIs! Laundrobots! Himself!), and even wetworks- it seems that there was a lot of darkness happening behind that shiny lifeless mask. It's the toxic alpha man/droid role Anthony Daniels has waited for his entire career.