(CNN) -- The presiding judge of the Texas Court of Criminal Appeals went on trial Monday, facing misconduct allegations over her refusal to accept a last-minute filing to delay an execution.

Protesters demonstrate outside the courthouse on Monday.

The State Judicial Commission has charged Judge Sharon Keller with failing to follow the court's execution-day procedures in the case of death-row inmate Michael Wayne Richard, and denying Richard access to open courts and the right to be heard.

Asked whether she would allow the court clerk's office to stay open past 5 p.m., as Richard's attorneys were having computer problems and might be late filing emergency paperwork, Keller refused to do so, according to the complaint filed against her by the judicial commission. Richard was executed that night.

In her response to the complaint, Keller maintained that she was asked whether the clerk's office stayed open past 5 p.m., and she "said no in accordance with long-standing custom." Watch why the judge is on trial »

"Judge Keller knew that pleadings had been filed after hours on execution days but not with the clerk's office," said the response. "She also knew that the general counsel, in this case Mr. Marty, stayed after hours on execution day." Keller knew that after-hours filings are provided for in the state's rules of appellate procedure, but also knew that regular office hours for state employees are 8 a.m. to 5 p.m. under state law, the response said.

District Judge David Berchelmann Jr. was appointed to preside over the hearing, according to judicial commission documents. Based upon his findings, the commission can take action ranging from dismissal of charges against Keller to her removal.

The afternoon of Richard's scheduled execution day, September 25, 2007, the U.S. Supreme Court announced it would hear oral arguments in a Kentucky case over the constitutionality of lethal injection. The court's general counsel, Edward Marty, had told judges that he had been informed by the Harris County prosecutors that Richard's attorneys were planning to file paperwork seeking to stay Richard's execution, according to the complaint against Keller.

At about 4:40 p.m. that day, Texas Defender Service, whose lawyers were representing Richard, called the court clerk's office and asked if their filing could be accepted a few minutes late, as they were having computer problems. The court's deputy clerk called Marty, who called Keller at home. The judge had left earlier in the afternoon to meet a repairman, according to the complaint.

Marty "asked her whether the clerk's office (or the court) could stay open past 5 p.m.," the complaint said. "Judge Keller said, 'No,' and asked, 'Why?' Mr. Marty replied: 'They wanted to file something, but they were not ready.' Judge Keller again said 'no.' "

Time magazine, citing a newspaper interview with Keller in October 2007 and pretrial testimony last year, reported Keller told Marty: "We close at 5."

"This execution proceeded because the highest criminal court couldn't be bothered to stay an extra 20 minutes on the night of an execution," Andrea Keilen, executive director of Texas Defender Service, told ABC News in October 2007.

Two other judges on the court told the Houston Chronicle they were willing to work late that night, and were unaware Keller refused to allow the filing of the appeal.

"It was an important issue," Judge Paul Womack told the Chronicle in the October 2007 story. He said he stayed at the court until 7 p.m. because "I wanted to be sure to be available in case it was raised."

Keller pointed out in her response that there were no written execution-day procedures in place the day of Richard's execution. She said she did not tell the other judges about her conversation with Marty because she thought they knew about it.

In a virtually unprecedented move, the National Association of Criminal Defense Lawyers in October 2007 filed a complaint with the State Commission on Judicial Conduct over the incident.

"To the best of my knowledge, this is the first time that NACDL has ever filed a judicial conduct complaint against a sitting judge," then-president Carmen Hernandez wrote. "Only a full and complete investigation of this incident will suffice. ... Whatever the findings of the judicial conduct commission, the handling of Mr. Richard's case -- and his death -- will remain unacceptable."

In her response to the charges, Keller also recounts Richard's case. He was convicted of sexually assaulting and killing a woman in 1986, months after he had been released from prison. By the time of his execution, Keller noted, Richard had two trials, two direct appeals -- one to the U.S. Supreme Court -- two state review proceedings and three federal review proceedings or motions hearings.

"The suggestion ... that Richard was not accorded 'access to open courts or the right to be heard according to law' is patently without merit," the response said.

In June 2008, the U.S. Supreme Court upheld Kentucky's use of lethal injection, ruling that the method -- used in 35 states -- is properly and humanely applied.

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