A legal challenge against Barnet Council’s outsourcing policy is “too late” and “unsustainable”, a court heard this afternoon.

Lawyers for the authority put their argument across for the first time after the lunch break on day two at the High Court.

Monica Carss-Frisk QC, for the council, urged the judge to dismiss the judicial review on the grounds it was brought out of time.

Ms Carss-Frisk said: “It can’t be right that the claimant should be able to delay until the very moment the contracts are about to be signed.

“The council has already spent nearly £5million, as well as wholly innocent third parties, who have spent large amounts of money on procurement.”

The applicant, Maria Nash, claims the authority did not properly consult residents on its decision to outsource core services – a decision she says will have an impact on people with disabilities, like herself.

The former holistic therapist brought the challenge in January after the council agreed a £320million ten-year contract to let Capita run its core back-office services.

The authority argues Ms Nash should have brought the challenge sooner and claimed she was “well aware” of the principles of the outsourcing scheme long before the contract was signed in December.

Applicants have three months following a decision to bring a judicial review.

The court and the council’s legal team spent some time this afternoon trying to establish whether the time limit began in March 2011, when outsourcing was first openly discussed, or in December 2012, when the contract was actually signed.

On the subject of consultation, the council initially appeared unable to convince Justice Nicholas Underhill it had met its minimum statutory duty.

The council claims it was under no obligation to carry out “specific or dedicated consultation”.

Justice Underhill said: “It seems to me to be exactly what the council should have done and is not very difficult.”

The authority argued that if it was made to carry out lengthy consultation on all issues it would be an “extreme burden”.

Justice Underhill later said he had not ruled out the possibility the council may be forced to go back and consult retrospectively. He said: “It’s not an attractive solution but you’d be stuck with it.”

The hearing will finish tomorrow (Thursday) but Justice Underhill may require more time before delivering a verdict in a case he said raised some “important questions” for other councils in the way they do business.