"What are you here for?" a police officer asks casually as he worries the handcuffs off Aaron Swartz's wrists.

"I don't know," Swartz replies. "I was riding down the street. Some guy took my bike, and I was arrested."

The exchange opens a 45 minute police booking video that shows Swartz at the moment his life began to unravel on January 6, 2011. Provided by the Secret Service in my ongoing Freedom of Information Act lawsuit against the agency, the video was recorded at the intake desk at the Cambridge Police Department, where Swartz had just been brought in on charges of breaking-and-entering into an unsecured networking closet on MIT's campus.

Swartz's arrest that day marked the end of a months-long cat-and-mouse game between MIT personnel and the activist, who had stashed a laptop computer in the basement closet to download millions of articles from the JSTOR academic database available free from the campus. MIT had captured surveillance video of the slender, nervous looking young man inside the closet, but didn't know who he was, until an MIT cop on the investigation recognized his suspect riding a bike on the streets of Cambridge and chased him down.

The arrest would lead to the federal computer hacking case that loomed over Swartz until his suicide in January of 2013. But in the video, Swartz is still trying to gauge the amount of trouble he's in. He's handcuffed to a rail for the better part of an hour while the cops go through what to them is the utterly routine, unhurried process of booking a prisoner.

Swartz surrenders his jacket and shoes, empties his pockets, acknowledges his Miranda rights. What kind of work do you do?, an officer asks him conversationally, while riffling Swartz's coat pockets. "I'm a research fellow," says Swartz. "I study corruption in Congress."

At eight minutes into the video, Swartz gets in an argument with the booking office when he refuses to provide his Social Security number.

Officer: "Do you know your Social Security number?"

Swartz: "No."

Officer: "How old are you?"

Swartz: "Twenty-four."

Officer: "And you don't know your Social?"

Swartz: "I don't use it."

Officer: "All right, what's your Social, man? I know you know your Social."

Swartz: "I don't know it.” Laughs.

Officer: "I'm going to find out."

Swartz: "Okay, well let me know when you find out.”

"I haven't memorized it," he adds, after a few more rounds. "Go ask my mom."

Swartz gives up his date-of-birth, but declines to provide his cell phone number or home address, says he doesn't know his height, and is ambiguous about his eye color. "Black? Brown?"

At the 27-minute mark, he presses for more details about why he was arrested. From his tone, he sounds surprised to learn that MIT is pressing felony charges.

Swartz: “So they said that I broke into MIT, is that it?"

Officer: "Yeah, they charged you with two counts of B&E in the daytime, to commit a felony."

Swartz: "At MIT?"

Officer: “Yeah.”

Swartz: "Huh. I mean, walking into MIT isn’t breaking-and-entering, right?"

Officer: “I have no idea what the circumstances are, man.”

Most people aren't at their best when being booked by police. Swartz was exactly at his best: asserting his rights in a casual, shlumpy posture that disarms his opponents without insulting them. Able to defy authority one minute, and joke around with it the next, the booking video is an exhibit in miniature of the qualities that made Swartz such an effective activist, and makes his loss such an enduring shame.

“You seem like a good kid, man,” the booking officer remarks, near the end of the process.

“I think I am,” says Swartz.

Disclosure: I knew Aaron Swartz and worked on a project with him.