Nikki Sinclaire, who represented the West Midlands region in Brussels and Strasbourg until 2014, is currently on trial for allegedly submitting "significant" expenses claims she knew to be false, according to the prosecution.
Sinclaire has alleged her expenses were submitted by her staff, and at least one claim was "deliberately corrupted" by a former aide, who was acting as a spy in her camp for the Ukip hierarchy.
Today, she told Birmingham Crown Court that in October 2009 Ukip called all its elected members together and briefed them about wrong-doing by then-MEP Tom Wise.
Wise admitted fiddling £36,000 of his Brussels travel expenses at his trial the following month.
The jury in Sinclaire's case has already heard how the first of what the Crown alleges were 10 dodgy claims date from October 2009 - the month of the Wise briefing.
Sinclaire, in the witness box, told jurors it would have defied sense for her to start filing false claims straight after being informed that Mr Wise, who represented the UK's East region, was being prosecuted.
She said: "All Ukip MEPs were called to either Brussels of Strasbourg, I don't remember which.
"We were briefed about Tom Wise, who was charged over expenses fraud - and what to say to the media if we were asked about it.
"The reason I say that is because the first claims of the allegations against me were right at this time."
She added: "Why would that be the time I would decide to start fiddling my expenses?"
Sinclaire's lawyers have claimed she did not deliberately sign off incorrect claims to gain financially, saying the total amount she could have made was "about 3,000 euro" - £2,465.
Sinclaire has also claimed at least one of her claims was "deliberately corrupted" by her former aide, John Ison - though he has denied any wrong-doing.
Jurors have also heard of several examples where she could have made genuine claims, including parliamentary trips to Cyprus and Cuba, which were never submitted.
The court has already heard about a background of party infighting, with "hostility" between Sinclaire and Nigel Farage.
Sinclaire lost the party whip as a result of internal disagreements in January 2010.
Jurors have also heard evidence from key prosecution witness Mr Ison.
Under cross-examination from her barrister Sean Hammond last week, Mr Ison accepted being a "spy or a mole" in her office, and he admitted passing information about the MEP to Nigel Farage in 2009-10.
Mr Ison also accepted making 30-40 hours of covert recordings of Sinclaire, but said he only acted "for the good of the party" during the period.
Mr Ison agreed that he also sent a message to another Ukip party member during a conversation about the MEP, saying: "Ok, Plan B - fraud."
On Tuesday, jurors heard that despite Sinclaire herself telling the EU anti-fraud unit of her suspicions about Mr Ison, no investigation was launched.
Sinclaire also contacted British police about her fears in September 2010, but was herself arrested in February 2012.
Unknown to her at the time, Mr Ison had reported her to the police in May 2010.
Asked by Mr Hammond why she made no comment in both her police interviews in February and October 2012, Sinclaire claimed she was just following her solicitor's advice.
She said that her arrest by West Midlands Police blocked her from rejoining Ukip - which she claimed had already been agreed. She then failed to get re-elected in 2014.
The 47-year-old, of Shirley, Solihull, West Midlands, denies misconduct in a public office between October 1 2009 and July 31 2010 while a serving member of the European Parliament by making or causing to be made false or dishonest claims for travel expenses.
She further denies a charge that between October 14 2009 and December 31 2010 she fraudulently transferred criminal property into her bank account.
The trial continues.