Deception & Debriefing in Research


The key over-arching principle in research ethics as it is discussed in the Tri-council Policy Statement: Ethical Conduct for Research Involving Humans (TCPS) is respect for human dignity, of which an important component is respect for free and informed consent; that individuals should be in a position to make a genuinely free and informed choice as to whether or not to participate in a research study.

In some research studies, however, disclosing full information at time of consent or at all, may introduce bias, nullify validity of results, or prevent the research from taking place. For these reasons, deception is sometimes required.

Deception with debriefing

Some types of research might entail less than full disclosure at the outset, but not involve actively deceiving participants with misleading information. For instance, a researcher might truthfully explain to a participant the general topic of the research, but not be able to explain the specific focus of the study at the outset, at risk of altering the phenomenon in question. Less than full disclosure at the outset should, in general, be easily handled by providing participants with a full explanation at the end of the study, in the form of a verbal or written debriefing, followed by re-consent. Issues that may need to be addressed through the debriefing include the following.

  • Privacy: A participant might reasonably feel that their privacy has been violated, if the researcher has collected information that the participant considers private, and not something they initially consented to. They might also feel that their privacy has been violated if the information collected is to be used to some other end than they would agree with
  • Misinformation: If a deceptive scenario deliberately misrepresents facts about real individuals, groups, or states of affairs in the world, the researcher has a responsibility to set the record straight. This involves not only clearly identifying which elements of the study were outright fabrications or misrepresentations, but also providing a positive statement of actual facts. This could be particularly important if the topic relates to issues that participants might reasonably be expected to consider important
  • Temporary and residual harm: If a deceptive scenario involves provision of false information that might be understood as applying to participants themselves, or to a group they belong to, the researcher should address and attempt to minimize any temporary negative arousal that might occur during the deception, such as frustration due to false failure feedback; the researcher should also address and attempt to minimize any residual misconceptions that might actually last beyond the period of the study itself.

To manage such issues, researchers should abide by the following guidelines, as suggested by the TCPS.

  • Studies involving active deception should have a clear and defensible scholarly motivation. Each of the deceptive elements of the study should be necessary, with a clear rationale to back this up
  • Participants should be provided with a complete, plain-language debriefing that explains very frankly:
    • which elements of the study were deceptive
    • why these were necessary
    • how the study relates to a broader, important area of knowledge
  • Once participants have been fully debriefed, they should be given the opportunity to re-consent to the use of their data, so it is clear that they have in fact given informed consent, and understand that they are otherwise free to withdraw their data
  • Research involving active deception should be relatively low risk and, should not involve therapeutic interventions, or highly vulnerable groups and sensitive topics.

Some additional points for researchers to consider are the following.

  • Initial consent: It is a good practice to make the initial consent process as informative as possible, keeping as much deception out of it as possible. To this end, it may make sense to mention explicitly that while it is not possible to fully explain the study in advance, participants will be provided with a full debriefing at the end.
  • Tone: A sensitive and informative debriefing can go a long way to mitigating possible adverse effects of deception. Participants should not leave feeling they have been duped. Researchers should work diligently to ensure that debriefings really are received and absorbed, using plain language with participants, about deceptive elements, and to situate the study in the larger area of interest.
  • Mitigating potential harms: Researchers should be sensitive to the fact that the specific focus of a particular study might relate to issues that are actually of some personal concern to participants. In situations where this is reasonably foreseeable then it would be a good practice for the researcher to have on hand contact information for relevant services or general background information so that participants can pursue any larger questions or issues raised by the study.
  • Training: Given the complexity and sensitivity of issues surrounding deception and debriefing in research, supervisors should work closely with students to provide training and raise awareness regarding good practices for the use of these methods.

If active deception is properly thought through and properly handled, it is not inherently unethical; participants who have been properly debriefed should be unlikely to find fault with the study, or to wish to withdraw from it. If participants do have concerns, however, they should be in a position to contact the Research Ethics Board (REB), and the researcher should work with the REB to address any issues.

Deception without debriefing

Certain types of research require striking a particularly delicate balance among contrasting needs for free and informed consent, accuracy and objectivity, and distance and criticality. Deception in the context of not revealing the researcher’s perspective or full intention should not be understood as an exception to the general principle of respect for free and informed consent; nor, however, should it restrict a researcher from conducting legitimate critical inquiry, provided that the researcher meets all of the requirements of TCPS Article 3.7A and B. Such issues should be carefully articulated in a protocol, and carefully navigated and negotiated in the field.

Other types, such as the audit methodology, may require that participants are never informed that they are actually involved in research at all. Such methods may be appropriate only in highly circumscribed scenarios, such as those in which privacy is not a legitimate expectation because the research is focused on public or commercial acts.

In situations where the researcher does not plan on debriefing participants and/or intends to not inform prospective participants that they are in a study at all, s/he must justify and the REB consider why this proposal is appropriate from potential harm and research feasibility perspectives. Researchers should provide a plan to disseminate information about the study to participants and their communities, if possible.

VPRI Contact


Dean Sharpe

Research Ethics Manager, Social Sciences, Humanities & Education
Research Oversight & Compliance Office (ROCO)
(416) 978-5585

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