Donald Trump's top expert witness appeared in the New York fraud trial Thursday in an effort to negate claims made by the New York Attorney General's office.

The NYU accounting professor, Eli Bartov, tried to paint Deutsche Bank as the responsible party for not doing due diligence in investigating Trump's finances when he applied for loans.

Trump and his associates are accused of inflating the value of their properties in an attempt to secure loans and insurance. The judge has already found them liable for fraud in a summary judgment, meaning the trial is largely aimed at determining damages.

Former FBI general counsel and ex-prosecutor Andrew Weissmann, speaking on MSNBC, called it absurd to place the blame on the bank, particularly given that it has already been proven that Trump lied so extensively on the documents.

He said it's fair to expect the bank to believe the official documents the company provided.

"I have to say I'm quite skeptical of the testimony from the expert about the long view, where it would include going against stated, documented things that Donald Trump had committed to in the deeds and the agreements, to say I'm just assuming all of that isn't true, without revealing all of that to the banks as to how he got to that appraisal figure," said Weissmann.

He also called out Bartov for testifying about whether there was fraud — expert witnesses are there to give their area of knowledge, not to give opinions on a trial.

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"As opposed to giving expert testimony about what the rules are in his view," he continued. "So, this was sort of an interesting day. It will be interesting, I think, mostly to see what, if anything, the state does to counter this evidence in their rebuttal case, because they have a chance to put on additional evidence when Donald Trump finishes his testimony on Monday."

He also criticized skirmishes between the expert witness and the AG's office.

"Those sort of side comments and sniping really should not be occurring, so this is sort of not the high road," Weissmann said. "But that is really up to the state that has the burden here to either undermine the testimony and to bring out facts, or to — they have a rebuttal case and they can put on additional evidence."

See the discussion in the video below or at the link here.

Legal expert debunks Trump expert's claim banks must do forensic investigations for a loanwww.youtube.com