Weiss, D. J. (2001). Behavioral and Brain Sciences, 24, 431-432.

This is a comment on the target article:

Hertwig, R., & Ortmann, A. (2001). Experimental practices in economics: A methodological challenge for psychologists? Behavioral and Brain Sciences, 24, 383-451.


Deception by researchers is necessary and not necessarily evil


David J. Weiss

California State University, Los Angeles




Despite claims of pure pragmatism, Hertwig and Ortmanns negative perspective on deception suggests a selfish psychologist willing to sacrifice the reputation of the discipline in order to expedite the research. While questions that appear to have correct answers may be investigated with complete openness, research that delves into personal secrets often requires deception as a tool to counter self-presentation bias.



From the participants perspective, there are two kinds of behavioral research. Hertwig and Ortmann seem to have considered only the class of experiments in which the task is to perform optimally in some defined respect. I refer to these as IQ tests. There is clearly a right answer, and the participant is asked to find it. Economists and some psychologists exclusively employ such tasks in their studies. IQ test researchers have traditionally seen little need for deception, and so can afford to seize the moral high ground.

The other class of studies consists of those that pry. The researcher wants to know some aspect of the participants character, attitudes, or personal history. If we presume that one of the participants main personal goals in any study is to come off looking good referred to as self-presentation bias (Catania, Chitwood, Gibson, & Coates, 1990), then we can see why the methodologies for the two kinds of research often diverge.

When there appears to be a correct response, the participant can do little to improve self-presentation other than try to get the right answer. On the other hand, when the research appears to be probing personal issues, then many participants inevitably try to hide attitudes or behaviors they think reflect badly on themselves. The researchers primary tools for countering these attempts to conceal are deception and privacy manipulation. It is important to note that the investigator cannot always specify the sensitive areas (Ong and Weiss, 2000).

For me, the danger is that the persuasive arguments raised by Hertwig and Ortmann will be used by the timorous APA to justify a blanket prohibition against deceptive practices. The other key variables they mention (scripts, repetition, and performance-based payoffs) seem to concern empirical issues, but deception is a different matter. Despite the authors explicit statement that they do not oppose deception on moral grounds, I am skeptical. The argument regarding the common good is clearly designed to inflict guilt on those of us who enlist deception in an effort to pry. Exposed trickery contaminates the pool of potential subjects, so that even the pure suffer for the sins of the miscreants down the hall. I liken Hertwig and Ortmann to vegetarians who, having failed to convince the carnivores that eating animals is evil, stress the health benefits of the ethical diet.

Continuing in metaphorical mode, I suggest that a superior analogy for deception is the medical communitys reliance upon antibiotics to combat bacterial infection. Each time an antibiotic is used, the likelihood of its efficacy in the future is reduced; but curing the current patient is deemed to justify this cost. New antibiotics have to be crafted on an ongoing basis to keep ahead of the microbes; so too behavioral researchers may need to create novel deceptions. The one-way mirror no longer works, so we abandon it. Of course, we always seek superior new methods; we are not committed to deception any more than the physician is committed to antibiotics. We use the most appropriate techniques available.

Even the IQ testing research community would be well-advised to be cautious regarding a ban on deception. In psychology, it has become routine to collect demographic information from our volunteers. Some participants may be curious as to why they are asked to provide their ethnicity or gender. That curiosity may lead to hypotheses that will affect the behavior under examination. Some will not want to reveal personal data, and circumventing that reluctance may call for subtlety.

People can be treated with respect even while they are being tricked (Saxe, 1991). What is important is that we do not violate our participants sense of self-worth. That is a subjective construct, to be sure, which is why the democratic institution of the Institutional Review Board can be so helpful.


Catania, J., Chitwood, D. D., Gibson, D. R., & Coates, T. J. (1990). Methodological problems in AIDS behavioral research: Influences on measurement error and participation bias in studies of sexual behavior. Psychological Bulletin, 108, 339-362.

Ong, A. D., & Weiss, D. J. (2000). The impact of anonymity on responses to sensitive questions. Journal of Applied Psychology, 30, 1691-1708.

Saxe, L. (1991). Lying: Thoughts of an applied social psychologist. American Psychologist, 46, 409-415.