A Cambridgeshire MP accused of plotting to avoid a speeding prosecution has told her trial that her fresh "leap" into national politics landed her with thousands of emails and working from a corridor.

Fiona Onasanya, 35, also told the court how she had assumed she was in Westminster on the day her car was caught by a speed camera, and that she had been diagnosed with a degenerative disease.

The Labour MP for Peterborough allegedly schemed with her brother to claim a Russian man was behind the wheel of her Nissan Micra when it was clocked doing 41mph in a 30mph zone.

The trained solicitor, who had been elected in Peterborough just over a month before the incident in July last year, gave evidence at the Old Bailey today (November 19) as she fights a charge of perverting the course of justice.

Onasanya's rise through politics

The churchgoer and former county councillor discussed her hectic rise through politics, joining a select committee four weeks after the general election.

"It was massive. It was more a leap than a step. I didn't have an expectation because I did not have any idea what it would be like," said Onasanya, who wore a blazer and black dress.

"It was a little but like being asked if you can swim and you say 'Yes, I can get by, I can swim', and then you get thrown in the ocean, it's not comparable."

She said that being whisked through the Westminster security process was "a bit like a freshers' fair" as she was given a laptop and iPad.

Asked how long it was before she had an office, she said: "I cannot remember the exact day because they had one committee room where everyone could be hot-desking or you could sit in a corridor."

Asked how busy her correspondence was in June 2017, she said: "As a new MP, when you get your laptop, iPad and security pass, they also tell you they have opened an email account for your Parliamentary email address."

The court heard that in July last year she had about 5,000 unanswered emails in her inbox.

"It's as if you had switched your phone off for a month and then you turn it on and the messages come through one after another," she added.

"When I started on June 12 and I sat down in the corridor thinking what do I do, how do I hire staff, who do I ask? When I turned in my laptop it started with 50 emails, then it jumped to 70, 100, 700. I had over 2,000 so that's just starting."

The MP, who was later promoted to the shadow whips office, also said that at the time of the incident she was unaware that her brother had nine points on his licence and had previously been disqualified for drink-driving.

The offence

Her car was caught by a speed camera on The Causeway, near the Cambridgeshire village of Thorney, at 10.03pm on July 24 last year.

A Notice of Intended Prosecution (NIP) was returned, naming the driver of her car as Aleks Antipow.

But jurors were told that Mr Antipow was at home with his parents in Russia at the time.

He previously lived in Chesterton, Cambridge, at a house rented by Onasanya and her brother Festus, the court heard.

It was also claimed that the contact address and phone number given were linked to Onasanya's 33-year-old sibling.

Festus Onasanya, of Chesterton, had previously deployed the same tactic, jurors heard, and he pleaded guilty to three charges of perverting the course of justice.

One of those counts related to the July 24 incident.

At that time he had nine points on his licence, three short of disqualification limit, and previous convictions for speeding, the court was told.

Onasanya told jurors how she would leave her car in Cambridge and spend four days a week in Westminster.

Her brother Festus, mother and others would sometimes drive her Nissan Micra, before it was written off following an accident, she said.

Explaining why singer Festus would borrow her car when he had his own, she said: "His car was often off-road having repairs and things done to it so he would use my vehicle.

Onasanya would sometimes let someone else drive her, she said: "Because of the nature of my work, sometimes because of a health condition I would be quite tired so I would be a passenger and also so I could get in with work if someone else was driving."

Prosecutor David Jeremy QC previously accused the MP of "lying persistently and deliberately" in a co-ordinated scheme with her brother to avoid prosecution.

The court also heard that, on February 3 last year, Fiona Onasanya had correctly filled out an NIP for triggering another camera a month earlier.

She kept a clean licence and avoided points by going on a speed awareness course.

A police investigation allegedly found that her two mobile phones were in the area of the traffic camera around the time it was activated on July 24.

Onasnaya recalled receiving a Notice of Intended Prosecution (NIP) letter relating to speeding on July 24.

Leaving the letter

She told jurors she had assumed she was at Parliament that day and left the letter for whoever was driving to complete.

"I jumped down to the date which was 24.7.17. I looked at my calendar on my phone and looked at what day the 24th was. I then folded back the letter put it back in the envelope, phoned my mum to say I've got a speeding something or other that's come through.

"I then left it at my mum's house. There's an area in the living room where we leave post for one another if it needs attention.

"I made the assumption at the time that I would have been in Parliament because it was a Monday and then I left it with the relevant person who would have known who the driver was."

She said she intended whoever was driving her car that day to complete the form, unaware it was her responsibility as the registered keeper.

But when she later received a letter saying the Russian no longer lived at that address, she spoke to her brother.

"When I spoke to him, I can't remember exactly, but paraphrasing him, he said it was sorted out," she told jurors.

The MP went on to tell jurors that she suffered a relapse of multiple sclerosis in September last year.

She said: "I probably was not in the best head space. I've just been told I had got an incurable degenerative disease."

Onasanya, from Peterborough, is on bail while the trial continues.