Sen. Cory Booker (D-NJ) appeared on MSNBC’s The Briefing Thursday, defiantly responding to recent attacks by President Donald Trump. Speaking with host Jen Psaki, Booker made it clear that threats — including the possibility of jail — won’t silence him. Psaki asked how Booker responds to Trump’s attacks and what message he has for whistleblowers or others afraid to speak out.

“Stand up and fight,” Booker said. “I’m going to continue to fight. I don’t care if this president calls me out every day, mean tweets me, threatens me.” He pointed to what he sees as a broader campaign of intimidation, citing the arrests of local Newark officials, including his own congresswoman, LaMonica McIver. “Throw me in jail. Do what you have to do. I’m going to continue to stand up for what’s right,” he added.

Booker’s call to action was aimed at inspiring others: “I’m hoping that when one person stands up and calls this out, it ignites the courage of another… We’ve got to have more people willing to stand up and fight and take him on.”

Rep. McIver, who represents New Jersey’s 10th Congressional District, is facing felony charges after allegedly assaulting ICE agents. She has denied wrongdoing, calling the charges “purely political” and racially motivated. If convicted, she could face up to eight years in prison and a fine of up to $250,000.

Prosecutors, however, insist the case is not political. “This isn’t about oversight,” said Acting U.S. Attorney Alina Habba. “It’s about respecting those who risk their lives to keep us safe.”