While I had several people reading the Hacker Crackdown stuff before posting it, I still got a couple of things wrong.
First of all, the three Legion of Doom guys in Atlanta were raided six months before the AT&T long-distance telephone network crash, but they weren’t arrested until three weeks after the network crash (along with Terminus, a Legion of Doom associate, and Knight Lightning, who edited the online magazine Phrack). Only after that did Erik Bloodaxe and the Mentor decide they had to take down their security research board, The Phoenix Project.

Here’s the best overall hacker crackdown timeline I’ve found online. The formatting isn’t great, though. I’ll probably make one at some point.

Also, thanks to Steve Jackson for pointing out that the U.S. Secret Service actually did have a warrant for Steve Jackson Games. What they didn’t have was a subpoena, and that was what cost them. This is because the Privacy Protection Act of 1980 grants publishers freedom from having the authorities search for evidence of crimes in their offices. Pete Kennedy was one of the lawyers for Steve Jackson Games, and he wrote:

they may not “search for or seize” publishers’ “work product” or “documentary materials”, essentially draft of publications, writers’ notes, and such. To get such material, the police must subpoena them, not with the much more disruptive search warrant.

Also, it turns out that the U.S. Secret Service had a warrant for their raid on Steve Jackson Games, though it was not available for inspection at the time of the raid or at any time soon after. It had been sealed by court order, which generally only happens when people’s lives are clearly at risk. Only many months later did Steve’s lawyers get the warrant affidavit unsealed.

The warrant, dated the day before the raid, clearly gives the SJ Games office address, even going so far as to describe it from the perspective of someone who had actually visited the location.

Mentor confirmed for me that the Secret Service agents already knew about Steve Jackson Games when they knocked on his door, and already planned on raiding the place. They mistakenly thought Mentor was a student at the university, which was why they’d brought campus police with them — likely because Erik Bloodaxe was a student. They did ask him about his past programming jobs, though it was when they tried working out his role at SJ Games that they learned about the cyberpunk game.

When I go back and edit the text — sooner rather than later, hopefully — I’ll work in all these changes and details.