Richards was executed hours after Judge Keller allegedly closed the court
A prominent judge in Texas has gone on trial accused of refusing to let lawyers for a convicted murderer on death row lodge a last-minute appeal.
Sharon Keller is charged with professional misconduct.
The prisoner, Michael Wayne Richard, was put to death hours after she allegedly shut the court, despite being told an appeal was imminent.
Half of all executions in the US last year were in Texas, where critics have dubbed Judge Keller "Sharon Killer".
She is known for her tough stance on the death penalty.
Just hours before his scheduled execution in September 2007, lawyers for Richard tried to lodge an appeal with Judge Keller, the presiding judge of the Texas Court of Criminal Appeals.
Their efforts were delayed by computer glitches and when they phoned the court to request extra time, they say they were told court closed at 5pm.
Richard, convicted of sexually assaulting and murdering a woman 20 years ago, was put to death by lethal injection some three hours later. He became the 26th person to be executed in Texas that year.
His lawyers allege that Judge Keller deliberately ordered the courthouse to close at 5pm, knowing a last-minute appeal was imminent.
The State Commission on Judicial Conduct said the judge had engaged in "wilful or persistent conduct that cast public discredit on the judiciary".
Judge Keller's lawyer says she meant that the court building closed at that time, but that there was an after-hours judge on duty who would have accepted the appeal.
"This whole case is about the confusion between the word 'court' and 'clerk'," Chip Babcock said, adding: "There is no question the clerk's office closes at 5pm. That does not mean there aren't after-hours filings."
It is common practice to keep the courthouse open in death penalty cases.
State prosecutors have charged Judge Keller with five counts of professional misconduct.
If found guilty, she could lose her position on the bench, a demotion that could end her career.