Clad in black and white, with hair to match, and approaching the bench in shackles, 28-year-old Simon Blackquill serves as the prosecutor for most of Phoenix Wright: Dual Destinies even while he serves a prison term for murder. His murder conviction is said to have ushered in the "Dark Age of the Law" during which the fabrication of evidence and pursuit of loopholes--a sinister practice previously employed by Kristoph Gavin in Apollo Justice: Ace Attorney--becomes rampant in the pursuit of courtroom victories. As is tradition with most other Ace Attorney main prosecutors, the background of Prosecutor Blackquill serves as a major driver of the larger story arc in Dual Destinies.
Prosecutor Blackquill uses what he calls the "power of suggestion" to psychologically manipulate witnesses (as well as the judge and his opposition), displaying a similar command over psychoanalytical techniques to that of defense attorney Athena Cykes.
He also frequently uses the way of the samurai to serve his metaphors and anecdotes when taunting the defense team or uncooperative / dimwitted witnesses. He will refer to defeating his legal opposition as "cut[ting them] down" and courtroom prowess as a "blade". When intimidating someone, he will spit the feature he holds in his mouth at his target and then slice it in half with a throwing knife that whizzes by the target's face. He will also, at times, send his pet hawk Taka to peck mercilessly at his target's head. (Taka can also be found perched on Blackquill's shoulder; perched on the judge's bald head; or fetching Blackquill notes.) At times, Blackquill will have his back facing the defense team as a sign of disrespect / intimidation.
Prosecutor Blackquill has an elder sister, Aura Blackquill. Their relationship is touched upon throughout the game's main story arc.