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Exercises for Machado

Some initial considerations in teaching this case

The Machado case looks simple on its surface, but when we unpack it, it becomes a complex weave involving multiple layers of action and inaction. There are multiple actors, including designers of the software, the computer personnel, and Machado himself.

This is not, however, simply the uniqueness of the Machado case, it is a property of all cases if they are studied closely enough. Finally, it is a property of the real life of technology in use. We provide here some exercises to help students grapple with the complexity of these situations.

But first a comment on simple answers. We recommend you read the section on pitfalls before teaching this case. It outlines ways to approach this case that bring only a shallow level of understanding to the complexities. In the Machado case, one of these pitfalls (affixing blame) leads to the tendency to think only about Machado’s action and its effect on the victims. But doing this leaves us outside of some places in the case where significant learning could occur. The decisions made by the computing personnel are useful models, as is the process by which the software Machado used was developed. We recommend you help your students look at more than just Machado’ action as they approach this case.


Analyzing Machado

This exercise uses a modified version of Robert Collins and Keith Miller's ParaMedic Ethics procedure. Collins and Miller recommend a procedure to use in evaluating a decision. We are not here evaluating any particular decision, but we can use their method to help us understand the obligations, rights, costs, and benefits for each of the parties in the system. This exercise will require students to read the case on the website with some knowledge of the method they will be using, so they can take relevant notes as they read. Thus, the best approach to this exercise requires introducing the modified paramedic ethics procedure in one class, assigning the exercise and case as homework, and then spending the next class period discussing students’ conclusions.

Alternatively, students might be assigned the case to read for homework and then introduced to the method of analysis in the subsequent class. If this approach is taken, be sure to have the case available in class (either on a computer with a projector or in printouts for each student) to aid recall.

There are several approaches to having students read the case for this exercise. You might have them read only the sections associated with UC Irvine, its computer center and personnel, and their actions. Once students have gone through the paramedic procedure based on their knowledge, you might then have them read the message itself and the background and description of Machado’ actions.

Alternatively, you might have different groups represent the Asian students who were targeted, the computer center personnel, and Machado. If you do this, you are likely to find the subjectivity in thinking about causes will become clear as the people doing the analysis from different viewpoints disagree with each other.

Each of these approaches are likely to produce differences in the way the case is analyzed by students. These differences help make it clear how important a comprehensive view of a case is.

Our modified paramedic ethic procedure consists of 4 phases. The basic analysis consists of phases 1 and 2, in which the basic relationships among the important stakeholders in the case are outlined. The phases that construct and judge the various alternative scenarios can be done as many times as you wish for each set of actions you think are important. To make this go faster, you might assign groups to construct and present their analysis of the duties and rights of each of the main stakeholders presented in the case: AECL, FDA, hospitals, operators, and patients.

Gather data

  1. List the relevant stakeholders. Start with some of the groups mentioned in the socio-technical system page. However, do not end there. Notice that our victims, the targets of the email, are not included. Other important groups may also be omitted (e.g. "other students, the public"). The ImpactCS framework provides you with a useful guide to different levels of stakeholders that you might overlook.
  2. Outline the duties and rights the stakeholders have toward each other. This is best done with a drawing of each stakeholder with arrows indicating duties one owes to other and rights one has. Duties always have targets, one has duties to a particular person (even to oneself). Rights may appear to be free floating (e.g. not to be harmed) but they can often be translated into duties that others have toward the individual (avoid harming X). The ImpactCS framework provides a useful guide to outlining these duties and rights. Use the list of ethical issues to remind yourself of rights and duties in the range of likely ethical domains.

Analyze the data

  1. List the relevant opportunities and vulnerabilities that each stakeholder had in the case. This is the beginning of what Collins and Miller call a utilitarian ethical analysis. Who is being helped and harmed? What advantages or opportunities does each party receive in this case? What costs or dangers, or vulnerabilities does each party experience?
  2. Determine to what degree each stakeholder's duties were fulfilled or neglected.
  3. Determine to what degree each stakeholder's rights were violated or protected, and by whom.

Construct an Alternative Scenario.

  1. Construct a promising alternative for some set of actions for a significant actor (e.g. alternative actions Machado might take to achieve his goals, alternative actions the computer center personnel might take, etc. ).

Judge the Alternative

    1. Judge the alternative's effect on each stakeholders' opportunities and vulnerabilities and on each stakeholders' duties and rights.
    2. Imagine each stakeholder in a negotiation with other stakeholders about whether the alternative should be adopted or not. This certainly helps uncover disagreements about the opportunities and vulnerabilities for each party. One interesting way to stage this negotiation is to have parties that initially represent each stakeholder attempt to don a "veil of ignorance" about which stakeholder they might be when the alternative is adopted. If you might be randomly assigned to any of the stakeholder roles in the case, how would this affect your evaluation of the alternative?
    3. Rank the alternative with other alternatives for that set of actions. An alternative does not have to be perfect, or even optimal, to be better than the others.

Collins, W. R. & Miller, K. W. (1992). Paramedic ethics for computer professionals. Journal of Systems and Software, 1-20.


Examining the RFCs for Ethical issues


The Supporting Documents section provides examples of several RFCs about both the finger protocol and SMTP. You might have students read these RFCs (or selections from them) to discover how ethical issues are easily associated with technical decisions. Different approaches can be taken from different takes on the RFCs. I provide some of these below.

Ohio State provides access to all the RFCs at

All the SMTP and MIME (another email protocol) RFCs are listed at:

We provide a copy of the earliest RFC for Finger and the most recent. The most recent finger RFC lists all its previous incarnations.



The original SMTP RFC has one section that is particularly interesting for our purposes: 4.1.1. command semantics. This section contains the description of the time stamp headers that were used to trace Machado’ email back to his original machine. You might assign groups of students to each take a likely command (e.g. RECIPIENT, DATA, VERIFY, EXPAND) and look at:

  1. The technical reasons for its presence and action
  2. The stakeholders who might be affected by the command
  3. The ethical issues for each stakeholder

This is really doing a mini case analysis for one of the commands in SMTP (see the advice for methods for case analysis). Students will have the benefits of about 20 years’ worth of hindsight in identifying issues associated with these commands.

This discussion will naturally lead to proposing alternative forms for the commands that avoid some of the ethical issues. Make sure to press students to defend the ethical reasons for their modifications, and to show they are beneficial (or at least not harmful) for all the stakeholders.

Finally, you might ask students to decide whether the original designer of SMTP could have foreseen the ethical concerns you are considering today.

An addition to this exercise could involve looking at other SMTP RFCs



The early Finger RFC can be used with an exercise similar to the one above for SMTP. Finger is a simpler command. And thus might provide a more easily structured exercise. You will find it particularly enlightening to compare the most recent version of the RFC with the original version that we make available here. .


All of these exercises might be done as in-class exercises or as individual homework and then discussed in the class.

Other Machado Exercises

Bill Frey and Jose Cruz provide many other exercises associated with cases from