In This Issue
Spring Bridge on Sustainable Smart Cities
March 15, 2023
The world’s cities face increasing threats from natural disasters, aging infrastructure, traffic, and resource constraints. The articles in this issue examine smart infrastructure, sustainability, net zero carbon options, and autonomous driving, among other approaches to smart and sustainable cities.

Invisible Bridges: (Un)intended Consequences

Tuesday, March 14, 2023

Author: Beth Cady

Engineering has contributed to many positive things, such as the supply and distribution of clean water, the automobile and airplane, and communications technologies from the telephone to the internet. But a deeper look at the Greatest Engineering Achievements of the 20th Century ( illuminates not only inequitable distribution of those achievements but also negative consequences for some communities. For example,

  • Highways were intentionally built in ways that destroyed Black neighborhoods and overpasses were constructed to prevent public buses from reaching the suburbs on Long Island.
  • Air conditioning and refrigeration benefit primarily those in high-income countries, but the climate changes associated with the chemicals used to cool ourselves and our food affect low- and middle-income countries far more than ours.
  • Electronics and appliances are eventually discarded in landfills, and many of the other technologies listed also require disposal of byproducts. The United States has a history of siting landfills, chemical plants, and other properties likely to result in negative health effects in low-income communities. And a 1987 study showed that, although “socioeconomic status was implicated in siting hazardous waste facilities, race was the most significant variable”[1]—approximately 60 percent of Black or Hispanic/Latine Americans and about half of Asian Americans, Pacific Islanders, and Native Americans live near toxic waste sites.
  • Nuclear technologies require uranium mining, which often occurs on reservations, poisoning Native communities and water supplies. It’s been pointed out that “collapsing environmental discrimination against people of color into one monolithic group elided the experience of Indigenous people who had been undergoing environmental devastation of a particular, genocidal kind.”1

While these consequences are often framed as “unintended,” they frequently are not. To paraphrase a joke about science, engineers can design a method for cloning a Tyrannosaurus rex, but humanities can tell us why that might be a bad idea. In other words, to avoid (un)intended consequences, engineers must work with other disciplines, incorporate other ways of knowing (e.g., Indigenous knowledge, non-Western traditions), and practice “epistemic humility—recognition that our way of knowing is not the only way of knowing.”[2] This recognition is critical, for “only by recognizing and being comfortable with the limits of their expertise can engineers actually help the people and the planet thrive, not just some people, on some parts of the planet.”[3]

Unfortunately, usual practice doesn’t follow this advice, which is why an “activist engineer” has been defined “as someone who not only can provide specific engineered solutions, but who also steps back from their work and tackles the question, What is the real problem and does this problem ‘require’ an engineering intervention?”[4] Not all problems require a technological solution. As made clear in the Law of the Instrument, a cognitive bias affecting all humans, “if the only tool you have is a hammer, it is tempting to treat everything as if it were a nail.”[5]

Framing the problem correctly requires reflection on these two questions, as well as consultation and/or collaboration with all communities who are or might be affected. Problem framing can lead to (un)intended consequences when the community that is affected is not involved in that framing and Indigenous, non-Western, and other disciplinary knowledge and ways of knowing are ignored. This is especially critical given the “intersectional privilege” of White, nondisabled, cisgender, heterosexual men in STEM fields,[6] because that privilege can lead to minimizing or overlooking the lived experiences of those with intersecting marginalized identities.[7]

Several guiding questions can frame problems in a way that will avoid (un)intended consequences and lead to engineering justice[8]: “What is placed into the problem? What and who is left out? Who draws the borders of what stays in and is left out and based on what assumptions and values? And whose perspectives (interests, values, knowledge, desires) are emphasized, de-emphasized, or ignored?”

When men dominate design teams and are assumed to be the end user for those designs—what has been called “one-size-fits-men”[9]—women suffer. For example, because many masks, boots, gloves, and other items of personal protective equipment (PPE) are designed solely using the “average man” specifications despite the need for women to use them, women experience more injuries and even death resulting from ill-fitting PPE than men do.5 It is well known that the first automobile airbags injured women; less well known is the fact that crash test dummies used for safety testing of cars have since the 1950s been based on the “average” male. Although an “average” female crash dummy was finally developed in 2011, it did not account for differences in muscle mass and distribution between men and women and was used only in the passenger seat, apparently assuming that women rarely drive.

To avoid (un)intended consequences, engineers must practice “epistemic humility—recognition that our way of knowing is not the only way of knowing.”

Ideally, engineers would follow the rule of “nothing about us without us,” which became part of disability activism in the 1990s.[10] Of course, most if not all engineered solutions affect a wide variety of users and stakeholders whose opinions about how the solutions would affect them are informed by their intersectional identities. Consulting with every possible end user would be time consuming and would also lead to conflicting information. However, it is critical for engineers to cast as wide a net as possible to inform solutions.

Diverse design teams are only part of the path forward, especially because many individuals do not feel they can bring their authentic selves to engineering.[11] For example, many LGBTQ+ individuals in STEM education and the workforce “struggle to be visible, to be heard, and to be recognized.”[12] Every engineered solution, policy, or cultural practice must strive for equitable outcomes, and “inequitable outcomes should be identified and characterized by [those]…that experience them.”8

Engineers would also do well to follow recent guidance issued by the White House on the use of Indigenous knowledge in federal decision making: “Since Indigenous Knowledge is often unique and specific to a Tribe or Indigenous People, and may exist in a variety of forms, Agencies often lack the expertise to appropriately consider and apply Indigenous Knowledge. As a result, consultation and collaboration with Tribal Nations and Indigenous Peoples is critical to ensuring that Indigenous Knowledge is considered and applied in a manner that respects Tribal sovereignty and achieves mutually beneficial outcomes for Tribal and Indigenous communities.”[13]

Humanitarian engineering, peace engineering, and other relatively new efforts address (un)intended consequences head-on. Hopefully these programs will eventually just be called “engineering” and not need a modifier that expresses work toward justice, because all engineering work and education will incorporate these ideas.

Inspired by the name of this quarterly, this column reflects on the practices and uses of engineering and its influences as a cultural enterprise.


[1]  Gilio-Whitaker D. 2019. As Long As Grass Grows: The -Indigenous Fight for Environmental Justice from Colonization to Standing Rock (pp. 16, 18). Beacon Press.

[2]  Riley DM. 2018. Foreword. In: Transforming Engineering Education and Practice, eds Leydens JA, Lucena JC (pp. xvii–xxi). Wiley–IEEE Press.

[3]  Cech E. 2012. Great problems of Grand Challenges: Problematizing engineering’s understandings of its role in society. International Journal of Engineering, Social Justice, and Peace 1(2):85–94.

[4]  Karwat DMA, Eagle WE, Wooldridge MS, Princen TE. 2014. Activist engineering: Changing engineering practice by deploying praxis. Science and Engineering Ethics 21:227–39.

[5]  Maslow AH. 1966. The Psychology of Science: A Reconnaissance (p. 16). Harper & Row.

[6]  Cech EA. 2022. The intersectional privilege of white able-bodied heterosexual men in STEM. Science Advances 8(24):eabo1558.

[7]  Intersectionality recognizes that individual identities are a function of the intersection of characteristics such as gender, race, ethnicity, socioeconomic status, religion, sexuality, appearance, and disability, among others. For example, a straight White man is likely to experience life and perceive the world differently from a Latina lesbian or a disabled African American veteran—or even a straight White woman.

[8]  Leydens JA, Lucena JC. 2018. Engineering Justice: Transforming Engineering Education and Practice (p. 20). Wiley–IEEE Press.

[9]  Criado Perez C. 2019. Invisible Women: Data Bias in a World Designed for Men (p. 157). Abrams Press.

[10]  See, e.g., NDI’s page “From ‘nothing about us without us’ to ‘nothing without us,’” Mar 28, 2022.

[11]  For example, see the interview with Lucy Yu in this issue (pp. 65–72).

[12]  Cross KJ, Farrell S, Hughes B. 2022. Queering STEM Culture in Higher Education: Navigating Experiences of Exclusion in the Academy (pp. 268, 278). Routledge.

[13]  Prabhakar A, Mallory B. 2022. Guidance for federal departments and agencies on Indigenous knowledge (p. 2). White House, Nov 30.

About the Author:Beth Cady is a senior program officer and director of the NAE program on Practices for Engineering Education and Research (PEER).