Over 11 days of testimony, jurors heard from 20 witnesses, who guided them through more than 700 exhibits, including hundreds of emails, documents and other materials. Prosecutors also played roughly four dozen secretly recorded telephone calls for the panel of eight women and four men — many between the senator and his son. The conversations included disclosures that, at times, were raw, embarrassing and even ludicrous.

Glenwood Management, a New York City real estate developer, was directed to funnel a $20,000 payment to Adam Skelos, and to help get him consulting payments at AbTech Industries, an environmental technology company, officials said. Another company, Physicians’ Reciprocal Insurers, gave Adam Skelos what amounted to a no-show job.

In his closing argument, one of the prosecutors, Rahul Mukhi, reminded the jury that there was no dispute that Adam Skelos had received the payments and that the senator had taken official actions on behalf of the companies that made them.

“So that leaves you with one key question,” Mr. Mukhi told the jurors, “which is this: Why did Adam Skelos get these payments?

“The evidence you’ve heard over the last few weeks establishes beyond a reasonable doubt that Senator Skelos got these payments for his son through his official powers, his official powers to make or break the companies that paid his son.”

The jury forewoman, Cynthia M. Nehlsen, 50, an antiques dealer from Westchester County, indicated that there was never a moment when the jury seemed split in its opinions. Ms. Nehlsen said the jurors had requested evidence and transcripts because “we just wanted to make sure of our decisions.”

A whiteboard was requested, she added in a later interview, so the jurors could draw a timeline of the Skeloses’ actions based on the closing arguments from prosecutors, whom she praised as “amazing.” The timeline made their decision a simple one: Although the jurors “really wanted to find some way that this wasn’t true,” Ms. Nehlsen said, the prosecutors’ case was virtually airtight.