A juror, who contacted a defendant via Facebook, has admitted contempt of court in the first case of its kind in the UK involving the internet.
London's High Court heard that Joanne Fraill, 40, contacted Jamie Sewart, 34, who had already been acquitted in a drugs trial costing £6m in Manchester.
Because other defendants were still on trial, the judge decided to discharge the jury, and the case collapsed.
Sewart was also found to be in contempt.
She had admitted the online contact took place but denied it amounted to an offence.
The case, brought by the Attorney General, Dominic Grieve QC, was heard by the Lord Chief Justice, Lord Judge, sitting with Mr Justice Ouseley and Mr Justice Holroyde.
Sentencing is expected to take place on Thursday.
The maximum penalty for contempt is two years imprisonment.
Lord Judge told mother-of-three Fraill, from Blackley, Greater Manchester, that she should expect to be sent to prison.
But he said he would not be able to decide on the length of the term until a linked appeal against conviction brought by another defendant in the case - who was potentially affected by her actions - was concluded.
He told Sewart, from Bolton, that any prison sentence on her would be suspended because she has a three-year-old child from whom she had already been separated during the crown court trial.
At the High Court hearing, Fraill admitted she had made online contact with Sewart and discussed the case with her while the jury's deliberations were continuing.
She also admitted revealing details of the jury's deliberations during that online conversation - contrary to Contempt of Court Act 1981 - and conducting internet research into a defendant whose case she was trying as a juror during the trial.
That was despite the judge reminding all the jurors that they must decide the case solely on the evidence given in court.
'Home and dry'
Fraill was on a jury in a case which had already been halted twice.
On 3 August last year, the judge in the third trial of the alleged drugs gang gave jurors the option of deciding the verdict by a majority rather than unanimously.
But the High Court was told the trial was stopped the following day when Sewart's solicitor informed the court that his client and Fraill had been in contact by Facebook.
The court heard the initial contact came after Fraill went on the social networking website and tracked down Sewart, saying: "You should know me - I've cried with you enough."
Fraill was said by her lawyer to have felt "considerable empathy" for Sewart as the trial ""gathered in momentum and intensity".
"Can't believe they had u on remand," she said in another one of their conversations, a transcript released by the court shows.
Fraill added she thought she recognised one of the other defendants and when asked by Sewart how the jury was dealing with one of the outstanding charges said: "Cant get anywaone to go either no one budging... don't say anything cause jamie they could cause miss trial".
The two continued to talk about the case and used expressions such as "lol" and other internet slang, as well as variants of spelling commonly used in such messages.
Frail also said: "At least then yer all home n dry".
And Sewart responded: "Ha ha, ur mad. I really appreciate everythin. If i cud of kissed u all i would of done ha ha."
She went on to say: "Keep in touch and I'll get u a nice pressie..."
The pair agreed to become Facebook friends after the trial.
Fraill also described her role on the jury in their conversations. "All that note-taking was just killing time. lol. drew more than i wrote lol," she said.
Solicitor General Edward Garnier QC told the High Court that that contact and discussion were in direct breach of the judge's repeated directions to the jury - and it constituted a contempt of court.
Peter Wright QC, for Fraill, said his client was terrified at the prospect of prison and was distraught and inconsolable about what she had done.
He described her as a woman of completely unblemished character before she "lost her senses" in the Facebook exchanges.
He said she only contacted Sewart because she saw in the younger woman's life her own.
"Her conduct, though reprehensible, was not calculated or designed by her to subvert the trial process, although it is conceded that that was an inevitable consequence of it," he added.
Leaving court, Sewart said she was "massively relieved" to be told she would not serve a custodial term.
She added: "I regret everything. She contacted me. My mind was in a whirlwind. I had just been acquitted. When I sat back and thought about it I realised I should report it and I did."