▶ Watch Video: A year after Capitol attack, former prosecutor talks about launching the investigation

With more than 725 defendants, the January 6 assault on the U.S. Capitol, is the largest federal criminal investigation in U.S. history. 

Michael Sherwin, then the justice department’s top prosecutor in the District of Columbia, helped launch the Capitol riots investigation.  

He told CBS News senior investigative correspondent Catherine Herridge that it was “important to move quickly to charge a good number of cases to instill in the public that the rule of law worked.” 

“Within 10 weeks, we’re talking about, I think close to 1,000 search warrants, 1300 to 1500 grand jury subpoenas. 350 to 400 arrest warrants, so just a number unseen before in any probably federal district in history.” Sherwin said. 

He said it didn’t matter who the person was — no one was off-limits when it came to this investigation. 

“It didn’t matter if you were a speaker that day or if you were a congressman, if you were in the executive office, if you were the president, or if you were just one of the vendors selling popcorn that day — if your conduct fit the crime, we had the evidence, you were charged,” Sherwin said. 

Since that day, more than 725 defendants have been arrested. The vast majority of those arrested were charged with entering or remaining in a restricted federal building or grounds. 
 
About 40 defendants — including Oath Keepers, Three Percenters and Proud Boys — face more serious conspiracy charges. At least five have pleaded guilty. Sherwin told CBS News the trend lines emerged early. 

“The great bulk of those individuals were these one-offs. They made terrible decisions. This wasn’t something that was prebaked. And then you have a sliver of cases, we’ll call them militia-type cases, where there appeared to be a more collective planning,” Sherwin said. 

Later that day, as then Vice President Mike Pence certified the electoral college, prosecutors mapped a legal strategy. 

“We initially had a command post set up that evening at the Capitol Police headquarters, where we had to set up an architecture to handle these cases to do that because there was no roadmap,” recalled Sherwin. 

From a mobile FBI command center, thousands of hours of social media and security camera footage were collected and often reviewed minute by minute.  
 
“We set up crews to look at body-worn camera footage and videos to try to identify who those people were — Identify, fix, find them and then get arrest warrants on them,” Sherwin said. 

Prosecutors say 140 police officers were assaulted that day and to date, more than 75 defendants have been charged specifically with “using a deadly or dangerous weapon or causing serious bodily injury to an officer”.

“Should the Capitol building have been locked down as a crime scene?” Herridge asked.  

“That would have essentially stopped the certification. So I think leadership wanted to ensure that look, let’s collect as much evidence as we can, but we have to show the public that this process hasn’t been deterred,” Sherwin said. 

Approximately 165 individuals have pleaded guilty—among them, the so-called “QAnon Shaman,” Adam Johnson and Robert Scott Palmer, who pleaded guilty to assaulting officers with a dangerous weapon was sentenced to more than 5 years in prison – the toughest sentence yet. 

Recently released data from the Justice Department shows the complexity and scale of the cases. The numbers of those who were arrested, charged, and pleaded guilty are not straight forward because of overlapping charges and the severity of the alleged actions.

The FBI is still asking for the public’s help to identify the pipe bomber who left viable devices at the republican and democratic party headquarters. 

“If those devices went off, you go from a terrible situation to a terrible situation on steroids,” Sherwin said. 

Another 350 believed to have committed violent acts on Capitol grounds are still wanted. Sherwin said it would not surprise him if there’s cases charged in 2022 or 2023. 

While the Justice Department has brought a range of charges including conspiracy and obstruction, it has stopped short of sedition, among the most serious crimes. 

Attorney General Merrick Garland is scheduled to provide an update on the department’s efforts to get accountability for January 6 on Wednesday.