The younger brother of the famous defense attorney Kristoph Gavin
, and a successful musician
, Klavier made his debut as a prosecutor shortly after the events of Phoenix Wright: Trials and Tribulations, where he faced Phoenix Wright
in trial. During the trial, he used a tip he had received in order to expose Phoenix Wright for using forged evidence, unaware that it had all been orchestrated by his older brother.
Seven years later, his brother was exposed for murder
by his own protege, Apollo Justice
, who promptly began working with Phoenix Wright. Klavier began facing Apollo in the courtrooms, and was defeated in their first meeting. After that, Apollo exposed Klavier's friend and bandmate Daryan Crescend
for murder and smuggling
. They met once again in court during a case that dated back all the way to his first case as a prosecutor, ultimately confronting Klavier with the fact that he had falsely accused Wright of forging evidence and that everything had been arranged by Kristoph.