Do violations of basic ethical principles in research invalidate the results of a study?

 

I don't think there is a clear yes or no answer to this. In theory, data don't automatically become "false" just because the study was done in an unethical way. The results may still be consistent with each other or even able to be repeated. But ethical violations often make us worry about how the data was collected, which in turn makes us less sure of and able to use those results. For instance, if participants were forced, not given enough information, or put in danger, that could change how they answer or act, which can lead to bias that isn't always clear. In certain instances, particularly in social research, the ethical violation is intrinsically linked to the validity of the data, as it influences the circumstances under which the data were generated. In addition to validity, there is the issue of whether these results should be utilized at all. Many would contend that utilizing findings acquired through unethical methods jeopardizes the validation of such practices, regardless of the perceived integrity of the data. This is why some studies that are important to history are still controversial, even though they have made important scientific contributions. So, even though ethical violations don't always make results invalid in a strict methodological sense, they do make the research less credible and less legitimate. In practice, this makes it much harder to use or build on these kinds of findings. 

 

 This isnot an easy question. Of course depends on what we considered as basic ethical principles. If we refer to scientific integrity in presenting results (e.g data falsification) these are definitely practices that should invalidate the results of a study. However, if you are talking about ethical principles related to the gathering and use of personal and sensitive data (as defined for example by GDPR), such as violation of privacy and not considering respect for communities, these do not invalidate the results but it is failure in considering ethical and legal issues in the study and if the results are to be published this is problem!  

This question cannot be simply answered with "yes" or "no", as there is no absolute, mechanical correspondence between violating basic ethical principles and the validity of research results. Strictly speaking, the scientific validity of research results - whether the data truly reflects the state of the research subject - and the ethical compliance of the research belong to two different dimensions: even if a study has serious ethical flaws, the data obtained may still be "accurate" at a purely empirical level. However, in the academic practice of contemporary population research, ethical violations almost inevitably lead to research results being considered "invalid" or "unacceptable" within the academic community.

This depends on what you mean by basic ethical principles. If you refer to scientific integrity (honesty and transparency) in reporting results, data fabrication of falsification, cherry picking, p-hacking .. these are definitely practices that should invalidate the results of a study. However, if you are talking about ethical principles related to the gathering and use of personal and sensitive data (as defined for example by GDPR), such as violation of privacy and not considering respect for communities, these do not invalidate the results but it is failure in considering ethical and legal issues in the study and if the results are to be published this is problem! 

Ideally, yes— but unfortunately, "basic ethical principles" doesn't invoke any particular codification. If you can reference a relevant professional society's established ethical code, then yes, that's what it's for, at least insofar as a given author identifies as a member of that society.