A juror weighing the fate of an accused rapist in Queens is in serious trouble after causing a mistrial by texting a pal about his intent to acquit.

That friend happened to be a Bronx prosecutor, who immediately informed the judge.

The two-week trial of José Fernandez, who is accused of sexually assaulting a woman the morning of April 18, 2009, blew up Tuesday as jurors were deliberating.

The unidentified juror texted the prosecutor that he wanted to give [José] justice and will vote not guilty, according to sources.

Queens Supreme Court Justice Richard Buchter was immediately informed and questioned the juror, who did not deny sending the text.

The judge then declared a mistrial.

The judge told the juror he could be cited for contempt, and he was instructed to return to court next Wednesday — with a lawyer.