The judge in the trial of Casey Anthony, the Florida woman accused of killing her 2-year-old daughter, mysteriously and abruptly recessed the case on Saturday morning saying only that “a legal issue has arisen.”

The jury in the closely-watched trial was set to hear more than five hours of testimony on Saturday with potential witnesses already gathered in the hallway outside. But the jurors were never brought into the courtroom.

Instead, Chief Judge Belvin Perry made his surprise announcement after a flurry of activity with counsel for both the defense and the prosecution. He said the trial would be in recess until Monday at 8:30 a.m.

IN PICTURES: Key players in the Casey Anthony trial

Most of the discussions took place in the privacy of the judge’s chambers, but apparently with a court reporter present to maintain a legal record.

The unexplained action touched off immediate speculation – virtually all of it uninformed.

Some wondered whether a possible plea deal might be in the works. Other analysts suggested the judge’s abrupt move may have been triggered by fresh allegations of violations of a court order that expert witnesses must disclose the full substance of their testimony in reports due earlier this year or face exclusion from the trial.

The judge has already cited Defense Attorney Jose Baez for willfully violating that order. Judge Perry suggested a second violation would be dealt with harshly.

At the close of proceedings on Friday evening, the lawyers raised two issues that might have expanded overnight into a trial-delaying problem for the judge.

One involved William Rodriguez, a Defense Department employee and expert in forensic anthropology and taphonomy, the study of human decomposition.

Dr. Rodriguez began testifying for the defense last Saturday, but his testimony was interrupted after prosecutors objected that he had not submitted a detailed report outlining his testimony in accordance with the judge’s earlier ruling. Rather than exclude his testimony, the judge ordered that prosecutors be given an opportunity to question him under oath in their office to discover what he would likely tell the jury.

In the meantime, someone at the Department of Defense learned of Rodriguez’s potential testimony and contacted Assistant State Attorney Jeffrey Ashton, one of the prosecutors in the Anthony case. The official told Mr. Ashton that Rodriguez had failed to obtain authorization to testify at the trial as a defense witness and would be fired if he did so.

Rather than get him fired, Defense attorneys dropped Rodriguez from the witness list. But they raised questions to Judge Perry about the circumstances of the Defense Department contact with Ashton. They also questioned why Ashton asked for, and received, an additional 24 hours to review Rodriguez’s deposition after he already knew Rodriguez was unlikely to testify.

The issue is potentially serious because any contacts made on behalf of the state attorney’s office with the intention of preventing Rodriguez from returning to the witness stand could amount to a form of witness tampering.

“I did not solicit this contact [with the Defense Department],” Ashton told the judge on Friday. “[The DOD official] informed me that they learned of Rodriguez’s testimony on television.”

The prosecutor added: “Any implication in counsel’s comment that I contacted them is absolutely 100 percent false.”

Baez told the judge that the defense team was investigating the matter. “We are going to have a motion regarding that, forthcoming,” Baez said Friday evening.

“If counsel wants to file something under oath, bring it on,” Ashton said.

“We will,” Baez responded.

The second issue that emerged late Friday involved the testimony of Yuri Melich, lead detective in the Anthony murder investigation. During testimony on Friday, Detective Melich revealed that investigators had obtained the cell phone records of Roy Kronk, the man who called police after discovering a small child’s skeletal remains in a wooded area not far from the Anthony’s home.

Melich said police obtained Mr. Kronk’s phone records from June to December 2008.

Ms. Anthony’s daughter, Caylee, was last seen alive on June 16, 2008 and her remains were discovered six months later on December 11.

That six-month date range is important for two reasons. It suggests that, at least initially, investigators suspected Kronk might be more than an innocent bystander who merely stumbled upon the gruesome scene.

Second, that date range suggested to Baez that state prosecutors had failed to turn those phone records over to him as court rules require.

Melich said he wanted Kronk’s cell phone records in part to track the locations where the phone had been used, including the call to police on December 11. Cell phone companies record which cell tower was accessed during each call, allowing investigators a crude means of tracking a suspect’s location after the fact.

Mr. Kronk is a big part of the defense theory of the case. According to Baez, Kronk called in a tip to police about Caylee’s remains in August 2008. But investigators never followed up by sending personnel to the scene. Baez has suggested that Kronk may have moved or disturbed the body before calling police again in December.

In his testimony, Melich said he subpoenaed Kronk’s cell phone records from June to December 2008.

“And did you turn over those cell phone records to the prosecuting attorney’s office,” Baez asked.

“Yes,” Melich said. “I would have turned over all records I got on this case to the state attorney’s office.”

After the jury was dismissed, Baez told Judge Perry that the defense had only received Roy Kronk’s cell phone records covering two weeks from June 16 until July. “We don’t have the rest,” he said. “I consider this a major violation if Mr. Melich was testifying truthfully.”

Assistant State Attorney Linda Burdick said she would check with Melich to ensure that all items had been properly turned over to the defense. “I am unaware of any intentional discovery violations, but I will continue to work with Mr. Baez to compare information,” she said.

Judge Perry said he didn’t recall the state trying to introduce phone records as part of its case against Ms. Anthony. “So that wasn’t an issue in the trial,” he said. “The only issue is whether those records are exculpatory and the state hid them.”

The judge said: “The bottom line is if you need records try to get them, but it is a little late in the day to be going after red herrings.”

After a moment, Judge Perry added, “If there are exculpatory things then you know what happens when they are exculpatory. And that’s all I’m going to say.”

Intentionally withholding exculpatory material from defense attorneys would be grounds for a mistrial if the harm was serious enough.

IN PICTURES: Key figures in the Casey Anthony trial