Briscoe, 56, a barrister from south-west London, has denied three counts of intending to pervert the course of justice.
The jury of six women and five men had been deliberating since Wednesday at Southwark Crown Court following two weeks of evidence, but were discharged yesterday after failing to reach verdicts on any counts.
Briscoe is accused of providing police with two inaccurate statements about her role as an intermediary between the then-energy secretary Huhne’s estranged wife, Vicky Pryce, and reporters in revealing details of the speeding points saga.
She is also accused of producing an altered copy of a statement and then deliberately getting a document expert to view the wrong version of the statement.
She will face a retrial, the court heard yesterday, but a date is yet to be fixed. If it goes ahead, it will be the fourth full trial to take place in relation to the original offence.
Pryce had faced trial for attempting to pervert the course of justice in February last year, but, as with Briscoe, the jury was unable to reach a verdict and a retrial was ordered.
Pryce was subsequently found guilty and, along with Huhne, who had already admitted to attempting to pervert the course of justice, was jailed for eight months in March. Both were released in May, but were subject to electronic tagging.
The jury in Briscoe’s case was reduced from 12 to 11 earlier this week after one member was discharged. But, after 13 hours of deliberations, it could not reach verdicts, despite being told that it could reach a majority verdict of 10-1.
During the trial, which started on 14 January, the jury heard that Briscoe helped economist Pryce, who was a friend and a neighbour, to reveal information about the points-swapping scandal to newspapers after she and Huhne separated in 2010. The scandal was to lead to Huhne’s subsequent prosecution.
It is claimed Briscoe misled police in two witness statements made on 31 May, 2011, and 16 August, 2012. When the allegations emerged in 2011, Briscoe was said to have made a witness statement to police in May that year, claiming Ms Pryce confided in her in 2003 after she found out that Huhne had asked her to take his speeding points, portraying herself as an “independent and objective” witness.
In a second statement in August 2012, she denied having any contact with journalists or newspapers about the story but emails obtained ahead of the Huhne-Pryce trial showed Briscoe had spoken to journalists. Once her involvement was revealed, she was dropped as a witness in Huhne and Pryce’s trial and arrested in October 2012.
It was claimed during the trial that Briscoe misled police in her witness statements. It is also alleged that she deliberately gave police an altered copy of one of the statements into which she had inserted an extra “I” to change the meaning to suggest she had refused to speak to journalists about the story – only for emails handed over by newspapers to prove she had been in touch with reporters.
The third charge alleged Briscoe then deliberately handed a different copy of the altered statement to an expert so he would find the alteration was due to a printer malfunction.