Trump attorney Susan Necheles began the proceedings by renewing their request that Judge Juan Merchan preclude parts of Stormy Daniels' planned testimony.

Necheles said that Daniels is expected to be the second witness today.

Prosecutor Susan Hoffinger argued that the context of the alleged 2006 sexual encounter between Daniels and Trump are important, though Daniels will not testify about that in detail.

"The details of the encounter, your honor, are important," said Susan Hoffinger. "In terms of a sexual act, it will be very basic ... how she came to have sex and how she felt about it."

"There is just no need for those kinds of details here," Necheles argued. "This case is a case about books and records, and we shouldn't get into how she felt about it, what happened in the room."

Judge Juan Merchan said he would stick with his earlier ruling allowing the testimony, but acknowledged that Daniels had "credibility issues."

"We don't need to know the details of the intercourse," Merchan said. "I agree with you that she had credibility issues."

Trump has denied that he had a sexual encounter with Daniels.

Proceedings are underway for Day 13 of Donald Trump's criminal trial in what is expected to be a dramatic day in the courtroom with the expected testimony of Stormy Daniels.

Trump is, as usual, seated at the defense table alongside his attorneys.

Todd Blanche and Susan Necheles flank the former president, and Emil Bove is at the far end of the table.

Donald Trump has entered the courtroom, looking at members of the press as he entered.

He is joined by his son Eric Trump and attorney Alina Habba.

In addition to approximately 70 members of the press in the courtroom, six members of the public are present in the courtroom to watch today's testimony.

They said they learned about the opportunity to watch the trial over the last few weeks and decided to come see the testimony for themselves. Some traveled from Los Angeles, Philadelphia, New Jersey and Brooklyn to attend the trial.

A court officer repeatedly reminded them not to fall asleep in the courtroom.

As Stormy Daniels described how she and Trump began having sex, Trump tapped his attorney Susan Necheles again, presumably to encourage her to object. Necheles then raised an objection about details of the sex, which was sustained.

Trump has steadfastly denied that he had a sexual encounter with Daniels.

"The next thing I know I was on the bed," Daniels said. "I had my clothes and my shoes off. I believe my bra however was still on."

Jurors seemed riveted -- a few were furiously jotting down notes, but most have their eyes fixed securely on Daniels.

"Do you remember how your clothes got off?" Hoddinger asked.

"No," Daniels said.

"Did you end up having sex with him on the bed?" Hoffinger asked.

"Yes," Daniels said.

"Did you touch his skin?" Hoffinger asked.

"Yes," Daniels said.

"Was he wearing a condom?" Hoffinger asked.

"No," Daniels said.

"Was that concerning to you?" Hoffinger asked.

"Yes," Daniels said.

Before detailing the sexual encounter, Daniels noted there was an "there was an imbalance of power" but she was not threatened.

"He was bigger and blocking the way. I was not threatened verbally or physically," Daniels said.

When it was over, Daniels said Trump told her, "We have to get together again soon."

She said he never expressed any worry about his wife finding out.