"We were very disappointed to hear Senator McCaskill's comments about the Guardian in an appearance on CNN yesterday," a Guardian spokesman said in a statement to The Huffington Post. "As an independent global news organization, it is our responsibility to publish material that is in the public interest."
"We reported these stories to stimulate an open debate about the tension between security and privacy," the spokesperson continued. "A debate best held in public."
On Thursday, McCaskill told CNN's Jake Tapper that she thinks "the Guardian has an agenda."
"I respect the fact that the Guardian is putting this information out there and that it's been leaked, I get that's the role of journalism," she continued. "At the same time there's been an awful lot of distortion around the facts of this information that's come to light and an awful lot of context that's been missing."
The Guardian has aggressively covered the NSA story over the past couple weeks, following up on documents provided by whistleblower Edward Snowden with extensive reporting.
McCaskill isn't the only member of Congress to criticize the Guardian. Rep. Peter King went much further in calling for columnist Glenn Greenwald to be prosecuted.
The last line of The Guardian's statement was slightly tweaked immediately after publication. The change was made at The Guardian's request.