Brixner became publicly known as part of the chamber that sentenced the justice victim Gustl Mollath to a forensic hospital, where he spent more than seven years.
In July 1998, after his appointment as chairman of the Nuremberg-Fürth district court, Brixner took over the chairmanship of the 6th Chamber of the criminal division, primarily judging invocations of drug related matters.
On the other hand, Brixner demanded in interviews with legislators to abolish life imprisonment and introduce temporary sentences of up to 40 years instead.
In September 2003, Gustl Mollath was accused of aggravated assault and false imprisonment to the detriment of his then-wife in a criminal case before the Nuremberg District Court.
Under the chairmanship of Brixner, the Nuremberg-Fürth Regional Court in August 2006 pronounced Mollath not guilty by reason of insanity, stating that, while the deeds were proven, the "lack of control capability [...] according to § 20 StGB [...] could not be ruled out".
Instead of punishment, Mollath was confined to forensic treatment in a closed psychiatric facility, as, according to the court, he continued to be a threat to society.
This was partly due to the conviction that his former wife, as an employee of the HypoVereinsbank, was involved in a complex system of money laundering.
Jurors and witnesses reported that Brixner acted uncontrollably during the trial and interrupted Mollath whenever he began to talk about the money laundering.
Juror Karl-Heinz Westenrieder said in a TV interview that Brixner had loudly interrupted Mollath and threatened to ban him from the courtroom whenever he mentioned tax evasion or money laundering.
[11] In mid-April 2013, Brixner reportedly confirmed that Martin Maske, the future husband of Mollath's former wife Petra, was already dating her during the 2006 criminal trial.
[14] Brixner was also repeatedly criticized for never taking note of the 106-page binder provided by Mollath and containing what he claimed to be exculpatory evidence.
[15] The outrage against Brixner was ignited by the fact that it is the fundamental obligation of all German courts to take full note of the case of the parties.