The Atlanta Public Schools test-cheating trial wrapped up its 18th week of testimony with an exchange between the judge and a defense lawyer that, once again, illustrated the toll the trial is taking on nerves and patience.

Robert Rubin is the first defense attorney to call witnesses. Twelve former APS educators are fighting charges that they engaged in a racketeering conspiracy to inflate scores on standardized tests, and lawyers for each are expected to call witnesses.

Prosecutors have portrayed Rubin’s client, former Dobbs Elementary principal Dana Evans, as a demanding and threatening leader who told teachers who couldn’t hack it that “Wal-Mart is always hiring.”

Defense witnesses countered that narrative, describing Evans as a “top notch” manager who was considerate to staffers and respectful to students.

But after almost a week of witnesses called by Rubin, Fulton County Superior Court Judge Jerry Baxter expressed frustration Thursday morning with what he saw as repetitious testimony.

“How many more of these witnesses are you going to have?” Baxter asked.

Rubin predicted he would still be calling witnesses on Monday.

“A full day of the same?” Baxter said.

“I don’t expect it all to be the same,” Rubin responded.

“At some point you reach a point of diminished return,” Baxter said.

“I’ve sat here for six months, listening to evidence,” Rubin replied, referring to the prosecution, which rested its case on Feb. 11 after calling more than 130 witnesses.

“I’m just making an observation,” Baxter said.

After the morning break, the judge apologized to Rubin.

“I feel bad about it,” Baxter said. “I think we need to have as much patience with these (defense witnesses) as we have for the state.”

Then Baxter added, “I’m just grouchy sometimes.”

The trial takes place Mondays through Thursdays, barring breaks for holidays, sick leave, bereavement, etc. Jury selection began in August, testimony started at the end of September, and the legal drama is not expected to conclude until late March or April.

Here are more highlights from Week 18:

MONDAY, Feb. 16

An unscheduled day off, courtesy of winter storm warnings that shut down the Fulton County courthouse.

TUESDAY, Feb. 17

While one defense attorney was questioning a witness, the sound of somewhat muffled laughter reached the ears of Judge Baxter.

He called on defense attorney Anne Greene, who represents former Dunbar Elementary teacher Shani Robinson.

“Yes, your honor?” Greene said.

“We can give you a minute to go outside and laugh,” Baxter said.

“Your honor, I don’t think anyone made any sound,” Greene responded.

“I can hear you,” Baxter snapped.

WEDNESDAY, Feb. 18

Kindergarten paraprofessional Bridgette Ukah made Judge Baxter and the jurors smile when she enthusiastically answered “Yeesss!” to the question: Do you remember the Dobbs Elementary School creed?

Then she recited it in a sing-song voice and used a finger to emphasize portions of her recitation.

“As I walk through the doors of Dobbs each day, I will strive to do my best in every way.

“I am committed to excellence and nothing less because I know my education is key to my success.

“I will respect my school and those who teach and guide me. I will respect myself and those who sit beside me.

“I will always do my share to show that I care. I am proud to be a Dobbs student.”

THURSDAY, Feb. 19

There was confusion as seven lawyers tag-teamed their argument against allowing the jury to hear a recording of one of the defendants yelling at her students.

The recording was an issue a few weeks ago when a prosecution witness said a recording she made of a lesson with a student also picked up former Dobbs Elementary teacher Dessa Curb yelling at some children.

When the topic of the recording came up several weeks ago, Baxter did not allow the tape to be played. But on Thursday, one of the prosecutors again raised the question of playing it after one of the defense attorneys asked how Curb was with her students.

One defense lawyer shouted Georgia law was violated when a conversation was recorded by someone who was not part of the discussion.

Another said the parents of each of the special-needs students in the classroom that day had to be notified because it violated federal law to discuss in public the personal information of those children without their parents’ knowledge.

A total of seven lawyers got involved.

“I’ve got about 10 people talking at the same time. Right, Evelyn?” Judge Baxter said to his court reporter.

“I didn’t get any of that,” she answered, even as some lawyers continued to talk.

WHAT’S NEXT

Robert Rubin is expected to call four more witnesses Monday to conclude his defense of former Dobbs principal Dana Evans, who told the judge Thursday that she would not be testifying.

Then lawyer Sanford Wallack is expected to call five or six witnesses in defense of former Dobbs Elementary teacher Dessa Curb.