As the investigation into Donald Trump’s Russia scandal intensifies, former FBI Director James Comey gave sworn testimony this morning before the Senate Intelligence Committee.

One of the questions that emerged yesterday is why Comey assumed Attorney General Jeff Sessions would have to recuse himself from the Russia investigation.

Does Comey believe Trump colluded with Russia? “It’s a question I don’t think I should answer in an open setting,” he replied.

The FBI had thousands of ongoing investigations, but Trump only spoke to Comey about one: the case against former White House National Security Advisor Michael Flynn, whose answers to the FBI about his Russia contacts, we now know, are also part of a criminal investigation.

Asked why he believes he was fired, Comey pointed to Trump’s confession to Lester Holt that the decision was based on the president’s objections to the Russia investigation.

Comey shared his concerns about Trump with Deputy Attorney General Rod Rosenstein, and then Rosenstein wrote a memo for Trump about Comey’s dismissal.

Assorted partisans and observers will look for morsels that bolster one argument or another, but the bottom line remains the same: Trump’s Russia scandal has reached a more serious level as a result of Comey’s testimony.