Alexandria, Virginia(CNN) The fourth day of Paul Manafort's trial blended tax documents with a witness' astonishing confession of guilt. Prosecutors are well into presenting hundreds of documents that they say show bank fraud, failure to disclose foreign bank accounts and tax crimes.
Here are four takeaways from the court action Friday:
In a courtroom, lawyers have various tools to make their points: video screens to show evidence, pointed questions to elicit certain answers and witnesses to speak about their firsthand knowledge of the alleged crimes. On Friday, the three legs of the evidentiary stool built a solid moment for the prosecutors.
RELATED: Accountants testify Manafort falsified loan documents, hid foreign income on taxes
The jury read damning email messages and documents to support the bank fraud charges. A witness said she had discussed creating fake documents with Manafort and longtime deputy Rick Gates, then sent the faked documents to a bank on their behalf.
She also testified that she knew her tax firm had fudged a loan amount so a then-broke Manafort could save up to a half-million dollars in taxes.
It's the closest this trial has come to smoking guns so far.
All three financial professionals who worked for Manafort -- the bookkeeper Heather Washkuhn and the accountants Philip Ayliff and Cindy Laporta -- sat through the same minute-long inquisition that appears to form the core of the prosecutors' foreign banking charges. Did you know Paul Manafort was affiliated with these companies? the prosecutor begins. He says one corporate name at a time, ending after 14 or 15. The witness says "no" to each.
Those are the offshore companies that prosecutors have already established paid for Manafort's personal excesses or "lent" him money.
The other thing prosecutors have established? That each of the financial professionals told Manafort explicitly and multiple times that he would break the law if he did not disclose his foreign accounts. He did not make those accounts known to them, all the witnesses said.
White-collar crime cases are notoriously hard to prosecute. This case has had hours of tax code explanation and tax returns, corporate financial accounting and the intricacies of loan, income and mortgage tax deductions.
Many a government attorney has lost a corporate financial case or had a mistrial because evidence became too dense, boring or confusing for the jury to follow.
Will Manafort's jurors face a similar result?
Throughout previous days and through Friday morning, some jurors grew fidgety or slouched in their chairs.
But when the prosecution neared the end of its questioning Friday, with the allegedly fake documents on the screen and a witness testifying to her own wrongdoing, the courtroom was rapt.
For three hours Friday, Laporta appeared to be a knowledgeable and careful accountant, describing with verve the way clients should report taxes and pausing to double-check evidence the prosecutors led her through. She came across as sincere -- even more so when she said that what she had done to help Manafort obtain bank loans was wrong.
"I very much regret it," Laporta said Friday. She testified that she had gone along with Manafort and Gates' allegedly fraudulent scheme because Manafort was a longtime customer of her firm, and she wanted to keep the firm out of immediate trouble.
In order for a jury to convict Manafort, Laporta's credibility must hold up. She'll be questioned by the defense team on Monday, and they've indicated to the court they'd like to raise the immunity deal she cut with prosecutors. Four more witnesses who have immunity -- meaning they, too, may have stepped out of line -- are positioned to testify. The defense may try to undercut their credibility as well.
Then, of course, there's Gates. He's already admitted guilt and to lying to federal authorities. Gates was a central player in passing the allegedly fake documents to banks, as shown Friday. He's certainly a key and coming witness -- one who could be impeached and pinned with crimes.
Prosecutors may have their own pocket ace on the Gates matter.
One of Manafort's defense lawyers sent prosecutors a statement after their client was indicted, creating a document that could destroy the defense's case. That document says Gates was "not involved" in some of Manafort's Cypriot banking. There isn't yet a resolution whether the jury will see that document.