Video report by ITV News Correspondent Ben Chapman
Labour has suspended Fiona Onasanya and said she should resign as an MP after she was convicted of lying to police to avoid a speeding charge.
The 35-year-old solicitor, who now faces a possible jail sentence, was accused of colluding with her brother Festus after her car was clocked going 41mph in a 30mph zone in the village of Thorney near Peterborough.
The Old Bailey heard evidence the MP for Peterborough was texting as well as speeding on the evening of Monday July 24 last year, during the summer Commons recess.
Prosecutor David Jeremy QC told the jury she went on to lie "persistently and deliberately" to avoid prosecution.
Festus Onasanya, 34, from Cambridge, had pleaded guilty to three counts of perverting the course of justice over speeding, including over the July 24 incident.
But his sister, who was elected in June 2017, denied a single count of perverting the course of justice.
The MP, who was elected in June 2017 but stood down as a Labour whip last month, was found guilty of one count of perverting the course of justice following a retrial at the Old Bailey.
A Labour spokesman said Fiona Onasanya had been suspended from the party and should resign as an MP.
He said: "The Labour Party is deeply disappointed in Fiona Onasanya's behaviour.
"It falls well below what is expected of politicians. She should now resign.
"Fiona Onasanya is being administratively suspended from the Labour Party and therefore the whip with immediate effect."
The Onasanya siblings face possible jail time when they are sentenced at the Old Bailey by Judge Nicholas Hilliard QC on a later date.
Fiona Onasanya defeated the Conservative incumbent Stewart Jackson at the 2017 election, winning with a majority of just 607 votes.