A Miami-Dade judge declared a mistrial in a murder case Wednesday after a defense lawyer posted a photo of her client’s leopard-print underwear on Facebook.

The defendant: Fermin Recalde, accused of stabbing his girlfriend to death in Hialeah in 2010.

Recalde’s family brought him a bag of fresh clothes to wear during trial. When Miami-Dade corrections officers lifted up the pieces for a routine inspection, Recalde’s public defender Anya Cintron Stern snapped a photo of Recalde’s briefs with her cellphone, witnesses said.

While on a break, the 31-year-old lawyer posted the photo on her personal Facebook page with a caption suggesting the client’s family believed the underwear was “proper attire for trial.”

Although her Facebook page is private and can only be viewed by her friends, somebody who saw the posting notified Miami-Dade Judge Leon Firtel, who declared a mistrial.

And Cintron Stern was immediately fired, according to Miami-Dade Public Defender Carlos Martinez, whose office represents clients who cannot afford a private attorney.

Clients are entitled to lawyers’ loyalty and respect, Martinez said.

“When a lawyer broadcasts disparaging and humiliating words and pictures, it undermines the basic client relationship and it gives the appearance that he is not receiving a fair trial.”

Also of concern to her superiors: an earlier post on her Facebook that appeared to call into question the client’s innocence.

Cintron Stern, a lawyer since 2008, could not be reached for comment.

The decision for a mistrial came after Recalde had sought, unsuccessfully, several times to fire his lawyers.

“In light of what took place in court, where the defendant was present and requested once again that his attorney be replaced, and considering the totality of the circumstances, the court granted that motion and also granted a motion for mistrial,” according to court spokeswoman Eunice Sigler.

This isn’t the first time the rapid rise of social media has vexed the criminal justice system – though problems at trial usually surface with jurors.

Judges across the country now routinely warn jurors about using the Internet, Facebook and Twitter during trials.

In April, the Miami-Dade Public Defender’s Office sought to overturn an armed robbery conviction after the jury foreman, Miami filmmaker Billy Corben, tweeted about his jury experience, although nothing directly about the case.

A judge declined to toss the conviction.

In 201l, the Arkansas Supreme Court threw out a man’s murder conviction and death sentence in 2011 after one juror repeatedly tweeted during the trial.

In September 2010, an appeals court threw out a manslaughter conviction of a Palm Beach County man after a juror used an iPhone to look up the definition of “prudent.”

In 2006, defense lawyers in an aggravated assault case against a pro football player sought to have a judge boot a prosecutor after he posted on his MySpace.com page links to news stories about the case. The defense claimed the prosecutor was trying to further his side gig as a South Beach DJ. He voluntarily stepped off the case.

Cintron Stern exhibited “shockingly poor judgment,” said Tamara Rice Lave, a University of Miami law professor who specializes in criminal procedure.

In today’s digital age, attorneys must recognize that their social media posts, even if meant to be private, can be damaging to their career, she said.

“But once it’s documented, everything is different. Once you’re a lawyer, your integrity and reputation are everything.”

As for Recalde, he is accused of fatally stabbing his ex-girlfriend, Dora Rial, during a jealous outburst. Rial, who worked at a Hialeah Hair Cuttery, had filed for an injunction for protection against an unemployed Recalde.

Rial’s teenage daughter was home when her mother was killed. The girl, now 16, testified Tuesday and now must testify again at a future trial.

Recalde, facing life in prison, was represented by Brian Kirlew and Cintron Stern, both assistant public defenders.

A new trial date, with a new lawyer, has yet to be set.