Holder sent Brownback a letter that basically said the state can't do that. "Kansas may not prevent federal employees and officials from carrying out their official responsibilities. And a state certainly may not criminalize the exercise of federal responsibilities," he scolded the governor.
Brownback didn't care for Holder's stern missive.
So he fired back with a letter of his own. (Read it here.) He responded with his own constitutional arguments.
"The people of Kansas have repeatedly and overwhelmingly reaffirmed their commitment to protecting this fundamental right. The people of Kansas are likewise committed to defending the sovereignty of the State of Kansas as guaranteed in the Ninth and Tenth Amendments to the United States Constitution," he wrote.
He also pointed to the bill's bipartisan support (not that broad support makes it constitutional): "The measure was adopted by a vote of 35 to 4 in the Kansas Senate with the Democrat Senate Minority Leader supporting the bill."
He closed the letter by asking that Holder take another look at the law. "The people of Kansas have clearly expressed their sovereign will. It is my hope that upon further review, you will see their right to do so," he wrote.
Now Brownback is no doubt breathlessly running to check the mailbox each afternoon, hoping for Holder's next letter.