Having some experience in the field of science, now engaging in also patent writing in various areas including chemistry, I can attest to the fact that as knowledge of the science evolves, especially for those skilled in the art, some reputedly 'new inventions' are more like near spontaneous logical leaps.
I have personally observed this many times, after getting a 'new idea', to discover pretty much the same invention already under a patent protection.
As such, claims of partial plagiarism, at least in the pure sciences, or even quasi-sciences like economics should, in my opinion, be taken with a bit of skepticism, and a country should not suffer an educational brain drain for what appears, from an outsider in a specialized discipline, as plagiarizing.
Here is an actual research article: "Plagiarism in medical scientific research", to quote from the abstract:
About five hundred articles were retrieved. Articles were divided into subgroups, with each group covering an aspect of plagiarism. Main findings and updates were summarized for each topic. The main reason behind plagiarism was found to be a lack of knowledge about the subject. When coupled with insufficient time, immature writing skills and the pressure on researchers to get their work published in good journals, authors take unacknowledged pieces of others' work and commit plagiarism.
which I would claim may encompass many cases of 'apparent plagiarism'. Even in the literary sciences, there is but a limited number of ways of saying something well. So, if two people happen to employ the same words that may, indeed, be simply a case of probabilistic coincidence.
Also, when a doctors makes medical mistake, they, as professionals, as judged by a panel of peers acquainted with the technical issues.
So, as to what should be the consequences for German, or other politicians, who seemingly plagiarized part of their PhDs thesis, nothing but a public report noting the possibility of said plagiarizing. Here is a report of what has occurred:
Allegations follow previous cases of federal ministers losing their government posts after evidence of plagiarism.
The Hannover Medical School in Germany is examining allegations that German defence minister Ursula von der Leyen plagiarized in her 1990 medical dissertation in obstetrics.
The allegations were made on the 'VroniPlag Wiki' website, a platform that searches academic theses for plagiarism. Compared to some of the cases VroniPlag has examined before, the alleged plagiarism is only "moderate", Gerhard Dannemann, a law researcher at Humboldt University in Berlin, told the magazine Der Spiegel.
In the past four years, two other federal ministers have lost their PhD titles and their posts in government following evidence of plagiarism: Karl-Theodor zu Guttenberg — also a defence minister — in 2011, and education and research minister Annette Schavan in 2013.
Speaking to German media, von der Leyen denied the scientific misdemeanour. The Hannover Medical School confirmed in a 28 September statement that it has launched a formal preliminary investigation, on the minister's request.
Please note the denial.