Margaret Merkerson said she changed Deerwood Academy students’ test answers in 2008 and 2009 to help out her friend Lavonia Ferrell. Ferrell said she did the same thing to help her friend Tabeeka Jordan.

But as investigations of the Atlanta Public Schools test-cheating scandal intensified, the friends turned against each other. Merkerson, at the request of GBI agents, secretly recorded phone calls to Ferrell to implicate her in the scandal. Ferrell testified Monday that she finally turned on Jordan, Deerwood’s former assistant principal, after an investigator from the district attorney’s office gave her one last chance to tell the truth.

Jordan, one of 12 former APS educators on trial for a racketeering conspiracy, continued to be the focus of the prosecution’s case Tuesday. She has previously denied directing Merkerson and Ferrell to cheat on the tests and said she would have reported them at the time if she knew they were changing answers.

During lengthy cross-examinations, defense lawyers challenged Merkerson’s and Ferrell’s credibility. They suggested the two former longtime APS educators were testifying against Jordan now so they would not be charged in the scandal and could keep their pensions.

On the witness stand this week, both Merkerson and Ferrell fingered Jordan, saying she orchestrated test-cheating at Deerwood in 2008 and 2009. Jordan helped them figure out the right answers on some tests, suggested more efficient ways to change students’ answers and covered up windows with construction paper so no one could see what they were doing, according to testimony.

In summer 2008, Ferrell, a testing coordinator, asked Merkerson, then a retired teacher, to come to Deerwood to help her get the Criterion-Referenced Competency Tests ready for the students. After tests were taken, Jordan asked the two women to erase and correct Deerwood students’ answers on the CRCT, both former educators testified.

In 2009, Jordan again asked them to change answers, the women said.

Merkerson and Ferrell, both of whom worked for decades at APS, declined to admit wrongdoing during initial state and school district investigations. But when GBI agents appeared unannounced one day at her door, Merkerson said she came clean and, in exchange for an immunity agreement, soon agreed to make secretly recorded phone calls to Ferrell without telling her friend she had implicated her in the scandal.

During one call, which was played to jurors Tuesday, Merkerson told Ferrell that GBI agents had offered her an immunity agreement if she told the truth. Maybe we could both get immunity because we’re in the same boat, Merkerson suggested.

“I just don’t want to go to jail,” Merkerson told her friend. “I’ll probably have a heart attack. … I want to be strong and be honest. I want to get my life back.”

Ferrell then told Merkerson she was going to put her on hold because Jordan was calling her. After a long pause, Ferrell clicked back to talk to Merkerson and told her that Jordan had just found out that Deerwood was the “only school they don’t have anything on” and that agents were saying they had evidence as a “tactic” to get people to cooperate.

Ferrell then told Merkerson that Jordan wanted her to “stand (her) ground.”

Only later would both Ferrell and Jordan learn that GBI agents, thanks largely to Merkerson, had made a case that cheating at Deerwood had occurred.

On Tuesday, Ferrell admitted that she lied to Merkerson on the recorded phone calls to try to keep her from telling agents what happened. Ferrell also said she initially lied to investigators to protect both herself and Jordan, whom she considered a friend. They went out to dinner and shopped together, and Jordan once came to her house at Christmas, bringing a pie, Ferrell said.

They also “talked about not telling actually what happened” when GBI agents started asking questions, Ferrell testified.

She admitted that even after she agreed to cooperate with prosecutors, she committed perjury when testifying against Jordan during a 2012 APS administrative hearing. She also said she allowed teachers to cheat on standardized tests when she previously worked at Fickett Elementary School.

At one point, Jordan’s lawyer, Akil Secret, told her, “We just want to be clear when you’re lying and when you’re telling the truth, Ms. Ferrell.”

Secret also asked Ferrell how she could be trusted now when she had lied so many times before.

“It’s my hope that they will believe me at this point,” Ferrell said, beginning to sob. “I don’t have any more reason to lie. It’s been seven years. … What else can you tell after you’ve told the truth? What can you say to make people believe you?”

Ferrell insisted that she was not coaxed by prosecutors into giving false testimony and said she was not testifying to get immunity or keep her pension. “It’s about my life from now on,” she said. “It’s about me.”

Ferrell said when she showed up to testify before the grand jury she saw Merkerson and apologized for getting her involved in cheating at Deerwood.

While that friendship appeared to be renewed, Secret questioned whether Ferrell had truly been a close friend of Jordan’s. At one point, he introduced into evidence an email in which Ferrell asked Jordan for her phone number, wondering why she needed it.

“Why would I?” Ferrell asked.

“She’s your friend.” Secret said. “… You said she was.”

“Is she now?” Ferrell replied.