Last week, the White House rescinded Acosta's hard press pass indefinitely after he physically stopped an intern from taking the microphone from him so another reporter could ask a question.
12 other news organizations have also come out in support of the "independent journalist", including Bloomberg and the Associated Press.
"Secret Service passes for working White House journalists should never be weaponized", the statement read. "This is just more grandstanding from CNN, and we will vigorously defend against the lawsuit", said Sanders in the statement. "We will be filing friend-of-the-court briefs to support CNN's and Jim Acosta's lawsuit based on these principles", the 13 news outlets said in their statement.
The White House had suspended Acosta's hard pass after he sparred at a news conference with the president, who demanded that the reporter give up the microphone and called him a "rude, awful person" when he did not immediately comply.
On Tuesday, CNN filed a lawsuit in US District Court in Washington, DC, seeking to have Acosta's so-called "hard pass" restored after he was banned for tussling with an intern during a news conference with President Trump.
Wallace followed, "While we don't condone the growing antagonistic tone by both the President and the press at recent media avails, we do support a free press, access and open exchanges for American people".
Even reporters who dislike Acosta's confrontational style have said presidents should not have the right to pick and choose which journalists participate in press conferences.
The dispute on live national television and Acosta's resulting banishment triggered a wave of accusations that Trump is stifling the free press, and marked a sharp escalation in tensions between the president and CNN.
The right-wing Fox News has been much more favorable to Donald Trump's presidency than CNN-where hosts like Don Lemon and Chris Cuomo have been persistent Trump critics-or the liberal-leaning MSNBC.
Acosta's press pass to access the White House was suspended "until further notice" after he engaged in the contentious back-and-forth last week over the migrant caravan working its way up through Mexico.
Speaking to reporters on Friday morning, Trump himself suggested the move had less to Acosta's contact with the intern and more to do with his volume.
Acosta did eventually surrendered the microphone, but the White House also suspended Acosta's press pass.
"While the suit is specific to CNN and Acosta, this could have happened to anyone", CNN said in a statement.
"I think Jim Acosta's been on Twitter the entire time - I'm not sure how his First Amendment rights are abridged".