A Jewish academic who says his union has not done enough to challenge antisemitism “deliberately misled” an employment tribunal, the union’s lawyer has claimed.

Ronnie Fraser was accused, by Antony White QC, of making around a dozen unreliable claims against the University and College Union.

The tribunal ended on Friday after evidence was presented from around 30 witnesses during the past three weeks. Its final session ended with the two sides’ legal representatives clashing over the reliability of those called to give evidence.

Mr Fraser’s lawyer, Anthony Julius of Mishcon de Reya, said he was “not going to rubbish the UCU’s witnesses in a retaliatory coup”, but said the approach taken by Matt Waddup, the union’s head of campaigns, to deal with antisemitism had been “extraordinary”.

Giving his closing statements at London Central Employment Tribunal, Mr White also accused Jewish Leadership Council chief executive Jeremy Newmark of lying four times in his witness statement, exaggerating evidence, and “wriggling like a fish on a hook under cross-examination”.

Mr Newmark had told the tribunal that at the union’s congress in 2008 he had been “targeted” by UCU officials who saw he was wearing a kippah and stopped him entering the conference hall. Mr White said the allegations were “simply false”.

Mr White also criticised Mr Julius, saying he had failed to put a number of allegations raised by Mr Fraser’s witnesses to the UCU’s witnesses when they were cross-examined. The UCU’s actions had been similar to those of a number of other unions and organisations which debated boycott motions, said Mr White. He argued that Mr Fraser had been a “player in the debate”.

In his own closing submission Mr Julius said the witnesses speaking on behalf of Mr Fraser had been presented because of the importance of having “a record of the issues, not because we think that the issues will be resolved in these proceedings by catching out one side or the other in a misremembered fact or event”.

Mr Julius said the union had “demonstrated an institutional incapacity to approach the issue of antisemitism appropriately and effectively”, and that Mr Fraser was seeking compensation “for injury to feelings” as the victim of harassment.

Tribunal chairman Anthony Snelson said the panel would meet for three days in the second half of January and again in February or March to review the evidence and prepare its judgment —which is not expected to be delivered before April 2013.