Did professor, co-author AND husband know Colzato was committing fraud? Leiden doesn’t want to know
The university has declared a complaint about psychology professor Bernhard Hommel inadmissible, even though the national integrity committee advised otherwise. As a result, there will be no investigation into any role he may have played in the fraud committed by his wife Lorenza Colzato.
Anoushka Kloosterman
Wednesday 28 June 2023

‘Now that the complaint is deemed inadmissible, the Board does not come to the balancing of interests to decide whether it wishes to investigate Accused’s role in the creation of the various publications’, writes Rector Hester Bijl in a letter to Leonid Schneider, who writes about integrity cases on his website For better science.

Last year, Schneider lodged a complaint about Hommel with the Committee for Academic Integrity (CWI) because he wants the university to investigate Hommel’s involvement in the fraud committed by Lorenza Colzato. This psychologist was dismissed from the university after three whistle-blowers raised the alarm about data manipulation, fabricated experiments and illegally taken blood samples from test subjects. A follow-up investigation into Colzato’s publications revealed that in 15 articles, data had been tampered with and subjects had been removed. In 7 of the 15 articles, the fraud was considered serious.

Hommel, Colzato’s husband and former scientific director of the institute, was either a co-author or the last author of four of those seven articles. That is why Schneider felt that Hommel’s involvement should also be investigated. However, the CWI ruled the complaint inadmissible because it was not concrete enough: ‘the circumstance that a co-author of the articles had committed fraud’ was not considered to be enough indication that Hommel himself had also violated scientific integrity rules.


The Netherlands Board on Research Integrity (LOWI) disagreed and said in its appeal that it ‘didn’t see’ why the complaint should be inadmissible. ‘If the Board does not wish to investigate the role of the Respondent (Hommel, Ed.) in this case, that is not the same thing as stating that the complaint was not defined clearly enough’, the national integrity committee ruled in a decision dated 22 February 2023.
And so, the LOWI advises the Board to handle the complaint. That does not mean that the university actually has to conduct the investigation - that is not for the committee to decide. But it does mean that the Board was advised to balance all interests, including those of the whistle-blowers and to justify why they would or would not initiate such an investigation.

‘Not wanting to investigate a complaint is not the same thing as stating that the complaint was not defined clearly’

The letter addressed to Schneider, which he has published in its entirety on his website, reveals that the university does not want to do that.

The Board thinks the complaint is not so much a complaint but rather a ‘request to investigate’, that has more ‘the characteristics of an investigative assignment’, writes Rector Hester Bijl. ‘Giving research assignments is reserved for the Executive Board.’ The Board also maintains its view that the complaint was too broadly formulated.

In addition, Bijl stresses in her letter that the investigation into Colzato’s articles was aimed at cleaning up the scientific literature and not at assigning blame. ‘It cannot be the case that in all events of demonstrated malpractice in publications, where one or more authors have been shown to have breached the scientific integrity, all other authors are therefore suspect without any further indication.’

However, in the next sentence she writes the following: ‘In the aforementioned CWI procedure, it has been demonstrated that the data manipulation took place in the transfer of data by junior researchers to the employee concerned, or during the analyses.’


This is surprising because the whistle-blowers had previously told Mare that the exclusion of test subjects was carried out under the pressure of Colzato, who ‘looked over people’s shoulder’ and ‘insisted they press the delete button’.
‘It was as if I had no other option’, one of them said at the time, regarding the power relationship between them. ‘I wasn’t confident enough to stop or to speak out against her, out of fear of negative consequences.’
Although the investigation was aimed at correcting the literature, it took a very long time before it became clear in which articles fraud had been committed. Initially, the university quietly published the completely redacted results of the investigation in some overlooked corner of its website.
Only after considerable criticism did the Board disclose the titles of the articles in which fraud had been committed. Whistle-blower Laura Steenbergen told Mare that she felt like she was ‘standing still’ due to this delay, and that all her publications would remain suspect until the list became public.
Hommel is still affiliated with Leiden University, but has been living in China with Colzato since October last year, where they work at Shandong Normal University in Jinan. Of the seven articles, four have since been withdrawn by scientific journals.