Vicky Pryce, a leading economist, and her ex-husband, the disgraced former cabinet minister Chris Huhne, both now face jail sentences after a jury condemned her as a liar and convicted her of perverting the course of justice on Thursday.

Pryce, 60, looked shocked and her jaw dropped as a jury rejected her defence of "marital coercion" and unanimously found her guilty of taking her former husband's speeding points 10 years ago.

The former joint head of the government economic service, who had nurtured political ambitions of her own with hopes of joining the Bank of England monetary policy committee and even the House of Lords, left court with her reputation in tatters. Despite her standing as a high-earning economist, who advised on the state of nations, Pryce chose to fight the case at Southwark crown court in London. Using her status as wife, she had claimed the archaic defence of marital coercion, maintaining Huhne, 58, then an MEP, had "pressurised" her into taking his points at the time as he was facing a driving ban.

But the jury of seven men and five women rejected that after about 12 hours of deliberations, deciding Pryce had a real choice when she signed a form saying she was driving his black BMW, H11HNE, when it was clocked on the M11 on 12 March 2003.

Huhne, the former energy secretary, pleaded guilty at the beginning of his trial on 4 February and resigned as MP for Eastleigh.

As her trial closed, senior Liberal Democrats quickly moved to distance themselves from Pryce, once a member of the party's elite, as her case raised questions over what deputy prime minister Nick Clegg knew of the scandal before it exploded in the press.

In emails between her and the Sunday Times political editor Isabel Oakeshott and which can only now be reported, Pryce claimed to have told what had happened to Clegg's wife, Miriam González Durántez, the business secretary Vince Cable, the senior Lib Dem peer Lord Oakeshott, who is a distant relative of Isabel Oakeshott, as well as "others working close to Clegg".

In one email, Pryce said she had told Cable, and his wife Rachel, over supper. "They were horrified at the time but VC has probably forgotten it by now. He was v tired that night," Pryce wrote.

Pryce's claims prompted vehement denials from the party, still reeling in the wake of the Lord Rennard scandal, in which Clegg has faced questions over what he knew of the allegations made by women of predatory behaviour by the party's former chief executive before it became public.

On Pryce's claims, a spokesman for Cable said: "Vince and Rachel have no recollection of the issue of points being raised with them over the course of dinner with Vicky Pryce on 28 January 2011. They have consulted their personal records which confirm that the issue first came to their attention in May 2011 when the story broke."

Sources close to Clegg said Pryce did mention to González as an aside at a business lunch with other people that Huhne had behaved very badly, but González did not inquire further because she assumed Pryce was referring to the events in their personal lives.

González added: "I have never ever been told by Vicky or anybody else about the traffic points story. I got to know about this when everybody else did."

Lord Oakeshott said: "Vicky must have been under a lot of pressure, but I am sure she never raised the points with me."

As Pryce was released on bail, judge Mr Justice Sweeney, warned: "Obviously Ms Pryce was present when I indicated to Mr Huhne the inevitable consequences of a conviction for an offence of this sort. She must be under no illusions that my granting of bail indicates any watering down of that provisional approach."

According to Crown Prosecution Service guidelines, the usual range of sentence is between four and 36 months, with "the degree of persistence" involved and the "seriousness of the substantive offence" taken into account.

Outside the court, Pryce stood impassively for photographers as her solicitor, Robert Brown, said: "Mrs Pryce is naturally very disappointed to have been convicted. She would like to thank all those who have supported her during this difficult process, particularly her children, her friends and colleagues.

"Mrs Pryce will return to court to be sentenced in due course. No further comment will be made until this is completed".

Pryce, a mother of five and a grandmother, was forced to stand trial twice, when a first jury was discharged having failed to reach a verdict. The two trials over five weeks laid bare her desperate mission to destroy her former husband in the press in revenge for his leaving her for his PR adviser Carina Trimingham, 46, who was then in a civil partnership.

She was helped by her friend, the prominent black female barrister and part-time judge, Constance Briscoe, 55, who may face charges over her involvement in the case. Briscoe, said to have been aware in 2003 that Pryce took Huhne's points, was dropped by the prosecution as a "witness of truth" and has been arrested after allegedly lying to police by claiming to have had no dealings with newspapers over the speeding story. Emails discovered later appeared to show she was in contact with the Mail on Sunday.

The jury heard Pryce embarked on a six-month campaign to "bring down" Huhne and "nail" him after his humiliating infidelity by trying to get the points story into the press without exposing herself to prosecution.

The trigger was her anger at being treated as a "scorned wife" in press briefings instigated, she believed, by Trimingham, when she attended the Lib Dem conference in September 2010.

Two months later, she and Briscoe were in contact with the Mail on Sunday, trying to "peddle a false story" that one of Huhne's constituency aides had taken his points, which was untrue and was not published. Pryce later went to the Sunday Times. In an effort to incriminate Huhne, but spare herself from prosecution, she secretly taped telephone conversations with Huhne, trying to goad him into admission. She had confidentiality agreements with both Sunday newspapers to protect her as a source.

Huhne had changed his plea to guilty on the first day of what was originally to have been the former couple's joint trial. The one-time Liberal Democrat leader hopeful, who is a multimillionaire with a property portfolio, now faces hefty court costs. The court hearings for both parties are estimated to have cost up to £200,000.

Malcolm McHaffie, of the Crown Prosecution Service said: "Chris Huhne made sustained challenges against the prosecution before pleading guilty at the last minute. This was expensive for the CPS and we will be applying for costs."