The woman was on the jury for a case about child abduction and sexual assault, the details of which she posted on her Facebook page, according to a report in The Sun.
She wrote on her webpage: "I don't know which way to go, so I'm holding a poll."
The juror was subsequently dismissed from Burnley Crown Court in Lancashire after an anonymous person reportedly informed the court about the content on the website.
She could have been charged with contempt of court, as jurors are not allowed to discuss details of cases to anyone, even family members.
The trial continued with 11 jurors, who found the defendants not guilty of child abduction and sexual assault, according to The Sun.