Here’s a quick summary of the FBI’s week: It came out that the agency probably let a bad guy go and charged a good guy with a crime.

The bad guy was Tamerlan Tsarnaev, who allegedly helped mastermind the Boston Marathon bombing on April 15.

It turns out that in 2011, the Russian government asked the FBI to look into any terrorist connections Tsarnaev might have had; the bureau, which receives an endless stream of such tips, questioned him but didn’t see anything suspicious enough to demand further action.

Not surprisingly, that doesn’t please some lawmakers in Congress, who have raised questions about why someone who was flagged as a potential terror threat was allowed to go free — and then allegedly committed an act of terror two years later.

The good guy was Paul Kevin Curtis, just your standard-issue Elvis impersonator, whom the FBI arrested for supposedly sending letters laced with the poison ricin to President Barack Obama, a senator and a judge. Except he didn’t do it.

“I heard the word ‘ricin’ for the first time in my life by a federal agent … and I thought he said ‘rice,’ ” Curtis told CNN’s Piers Morgan. “I said: ‘I don’t even eat rice, usually. I’m not even a rice lover.’ ”

Between Tsarnaev and Curtis, the FBI went 0 for 2. And that’s not good enough.

The FBI, for swinging and missing (twice!), you had the worst week in Washington. Congrats, or something.

Chris Cillizza covers the White House for The Washington Post and writes The Fix, its politics blog.