Vaccination and the Freedom to Choose

What is the argument against vaccine mandates? Katharine Browne argues that right to bodily autonomy trumps, in this case at least, concern for public safety.

What is the argument against vaccine mandates? Katharine Browne argues that right to bodily autonomy trumps, in this case at least, concern for public safety.


Vaccinations are important – arguably, the most important – public health interventions. They have eliminated or greatly reduced a host of infectious diseases and, in our current context, promise to help put the worst of the coronavirus pandemic behind us.

In Canada, mass vaccination efforts against COVID-19 began on December 14, 2020, with priority given to older Canadians and front-line workers. But while the majority of Canadians jumped at the opportunity to become vaccinated against COVID-19—some of them waiting in line for hours at pop-up vaccination clinics across the country—many didn’t. At the time of writing, 77.79% of the population has been vaccinated with two doses against COVID-19((Our World in Data, Statistics and Research: Coronavirus (COVID-19) Vaccinations, https://ourworldindata.org/covid-vaccinations?country=OWID_WRL)). This leaves 22.21% of the population not fully vaccinated.

Setting aside those who cannot (for reasons of age or medical condition) get vaccinated, reasons why people refrain from becoming vaccinated are varied. The bulk of the blame typically falls on the anti-vaccine movement and conspiracy theorists. But this is to ignore other reasons for low vaccination uptake. For some, it is a matter of access. For example, barriers – such as one’s geographic location or a lack of flexibility in one’s job or childcare – sometimes make access to vaccination difficult. For others, it is a matter of trust in public institutions. Many individuals in this category come from marginalized groups who have previously felt let down by the public institutions that ought to support them.

Canadian vaccination coverage is relatively high compared to other countries. Only 62.33% of the U.S. population, by contrast, is fully vaccinated((Our World in Data, Statistics and Research: Coronavirus (COVID-19) Vaccinations, https://ourworldindata.org/covid-vaccinations?country=OWID_WRL)). However, vaccination rates—in Canada and worldwide—remain lower than is needed to keep the spread of coronavirus low. Add to this waning immunity of those who are vaccinated, and the emergence of the highly contagious Omicron variant that escapes immunity from two doses, and vaccination efforts—and now booster campaigns—are ever more urgent.

As a result, there is growing momentum in some countries towards making vaccination mandatory. In Canada, there is a requirement that most federal public servants be fully vaccinated, and mandates for the wider population may soon follow. Quebec, for example, has recently announced a tax on the unvaccinated. Beginning in February 2022, residents of Austria will be required to become vaccinated, on pain of fines of upwards of 3600 Euros. Greece will begin fining individuals over 60 years of age who do not become vaccinated. And Germany will soon vote on whether to make vaccination mandatory, despite earlier assurances that such mandates would never be implemented.

Is mandatory vaccination ethically justifiable? (I will here ignore the question whether it is practically efficacious. Some concerns have been raised, for example, that mandating vaccination will be counter-productive and decrease vaccination uptake. Whether or not mandatory vaccination is practically efficacious, it is important to ask whether it is ethically acceptable.)

Opponents to mandatory vaccination will challenge the extent to which the state has a right to interfere with their liberty to make choices concerning vaccination. And, indeed, while vaccination is an important public health intervention, what is unique about it is that it is also a medical intervention. In other contexts, the decision whether to accept medical treatment is left entirely up to a decision-capable individual. This is grounded in respect for individual bodily-autonomy, which one might take to hold a higher significance than other liberties.

…justifying mandatory vaccination by appealing to the prevention of harm to others is not as straightforward as it might first appear.

Proponents of mandatory vaccination will argue that individual liberty is not absolute and can be set aside in order to protect others from harm. These proponents will argue that remaining unvaccinated poses sufficient harm to others, and this justifies overriding individual liberty.

But justifying mandatory vaccination by appealing to the prevention of harm to others is not as straightforward as it might first appear. This is because, as we will see, it is sometimes difficult to pinpoint a clear and distinct serious harm that any one individual’s refusal to become vaccinated poses to others. We are left with what I take to be an irreconcilable tension between individual liberty and the aims of public health, and the hard choice of subordinating one in the service of the other.

Mandatory Vaccination and Individual Liberty

While vaccines are now available in Canada and other parts of the world to children aged 5 and older, I will confine my focus here to the question whether mandates for vaccination against COVID-19 for adults is justifiable. This is because the arguments that appeal to the value of individual liberty which will be our focus require that individuals be of a certain maturity of mind to make decisions on their own behalf.

It is first important to clarify what counts as mandatory vaccination. In the public discussion surrounding vaccination regulation there are gradations of what counts as a vaccine mandate. At one end of the spectrum we have Austria’s newly introduced mandate, which requires that individuals become vaccinated or face financial penalty. At the other end of the spectrum are rules like those found in Germany, which require that persons be vaccinated, recovered from a COVID-19 infection, or tested in order to enter non-essential businesses.

It is not clear that all regulations concerning vaccination are instances of mandates. For example, there is a relevant difference between a rule that allows an individual to choose between being vaccinated or tested and a rule that bars an individual from accessing a service unless they have been vaccinated or recovered from a COVID-19 infection. The former arguably does not qualify as a mandate, insofar as a significant degree of choice remains, whereas the latter may.

I will here understand “mandatory vaccination” broadly to include policies that impose on the unvaccinated some kind of serious penalty that makes normal participation in society difficult or impossible, which can take the form of legal sanction (e.g., imprisonment), financial penalty, or withholding of an essential social good or service such as school or employment. On this understanding, barring an unvaccinated individual from going to work or entering a grocery store counts as a vaccine mandate, insofar as these are essential social goods or services. Preventing an unvaccinated person from dining in a restaurant, however, does not.

The strongest case that can be made against mandatory vaccination appeals to individual autonomy. Autonomy refers to an individual’s capacity for self-rule, or to make important decisions concerning their own lives.

A staunch defender of individual autonomy was John Stuart Mill. Mill held that state interference should be kept to a minimum, and sought to secure for the individual a maximum latitude of freedom. Mill was a utilitarian. He thought that the rightness or wrongness of actions was to be judged solely by the consequences of those actions. The priority he placed on individual freedom and limited state interference is justified by the consequences of doing so.

Mill thought that better consequences would obtain for everyone if there were a rigid rule against interference with an individual’s autonomy by the state. He thought that individuals were better situated than anyone else to make decisions concerning their own lives, and that interference on the part of others would generally do them a disservice. He also thought that allowing individuals the freedom to make choices enhanced their capacity as choosers.

There are also non-utilitarian justifications for respecting individual autonomy. Immanuel Kant, for example, held that interference with an autonomous agent’s choices was a failure to respect individuals as rational agents.

The prioritization of individual autonomy is reflected, in the context of medical decision-making, in the doctrine of informed consent. Medicine was once dominated by the Hippocratic tradition. This model of care assigned to the physician the role of expert and the job of administering treatment they thought best for the patient. It was assumed that the doctor knew best, and that the patient ought to comply with the doctor’s orders, often without much knowledge about the nature of the treatment prescribed.

This Hippocratic model has since been replaced by the patient-centred model of care, where patient autonomy reigns supreme. On this model, decision-capable individuals are able to decide what happens in and to their bodies. That a patient can refuse any medical intervention is taken to be an inviolable right. This includes decisions that are thought not to be in the individual’s best-interest or what is medically best. For example, a decision-capable cancer patient can refuse life-saving chemotherapy because she does not want to endure its side-effects. A decision-capable Jehovah’s Witness patient can likewise refuse a life-saving blood transfusion on the grounds that it conflicts with their beliefs.

Moreover, in some cases, a right to bodily autonomy is thought to trump potential rights of others. Indeed, some liberal views concerning the permissibility of abortion will hold that a woman’s right to bodily autonomy is absolute, and trumps even any rights a fetus might have.

If we treat vaccination against infectious diseases as we do other medical interventions, then the decision whether to vaccinate should also be governed by the doctrine of informed consent. Just as the cancer patient can refuse life-saving care for whatever reason they deem appropriate, so too should an individual be able to refuse a vaccination on any grounds they cite. We thus arrive at a presumptive case in favour of choice concerning vaccination.

Harm to Others & the Limits to Liberty

The strongest case in favour of mandatory vaccination appeals to the potential harm to others that remaining unvaccinated has. Even those who strongly endorse respecting individual autonomy will contend that sometimes an individual’s liberty can be restricted if their choices are potentially harmful to others. As Mill famously said:

…the sole end for which mankind are warranted, individually or collectively, in interfering with the liberty of any of their number is self-protection((J.S. Mill, On Liberty (1859), Ch. 2, para. 9)).

Mill held that the only justification for the state to interfere with individual liberty was to protect others from harm. This harm needs to be substantial and a likely outcome of an individual’s actions. Thus, if it can be demonstrated that one’s failure to become vaccinated will likely result in substantial harm to others, then even those committed to respect for individual autonomy must concede that restrictions on liberty are permissible. This invites the question: are vaccine mandates necessary in order to prevent harm to others? There are two different types of harm that the unvaccinated risk posing to others.

The first is direct. An unvaccinated individual is more likely than a vaccinated individual to become infected with the illness and to pass it on to others. In such cases, the unvaccinated individual would be directly responsible for the harm posed to another. But it is important to note here that the actual harm posed by the unvaccinated individual requires, first, that an individual become infected with the virus and, second, that they encounter someone who is liable to become infected. That person must also become infected and be subsequently harmed by the virus. There are thus a number of degrees of separation between actual harm done to others and remaining unvaccinated.

In terms of the application of the harm principle, the unvaccinated are often treated as if they were already infected. But there is a difference in the level of risk of harm posed to others by someone who is already infected and someone who only liable to become infected. The former case presumably justifies a higher degree of interference than in the latter case, because of the higher risk of harm to others that is involved. In the event that one is already infected, mandatory quarantine would be justifiable by the harm principle, to the extent that such an intervention would prevent immediate harm to others. But it is not obvious that the mere fact that one is has the potential of becoming infectious (and thus pose a risk of harm to others) is a significant enough consideration to override liberty, even if that potential to become infectious and thus harmful is greater than it would be if one were vaccinated. The difference lies in the fact that the harm posed by the unvaccinated is merely potential and not immediate.

The second type of harm is indirect. An individual indirectly poses a risk of harm to others by failing to contribute to the collective effort of vaccination. As the current pandemic has made clear, a large enough proportion of the population needs to become immune – either through vaccination or recovery from an infection – in order to limit the spread of the virus. Herd immunity refers to the point where an adequate number of individuals is immune in order to prevent significant spread of the illness through the population. Herd immunity is particularly important in providing indirect protection to those who cannot—because of medical- or age-related reasons—become vaccinated themselves. The proportion of the population that needs to be immune will vary depending on how infectious the illness is. There is some uncertainty about what proportion of the population needs to be immune in order to achieve herd immunity in the case of COVID-19. It was first estimated that 60-70% population needs to be fully immune for there to be herd immunity, but experts now estimate this number to be higher. What is clear is that by refraining from vaccinating, one fails to contribute to the production of herd immunity. And if enough people refrain from vaccinating, whatever protection is provided by herd immunity will drop and the virus will begin to spread more rapidly through the population.

There are thus direct and indirect harms that an individual may pose to others by refraining to vaccinate. But how much harm does an individual risk posing to others? This will depend on how many others in the population are vaccinated.

When there is herd immunity (or where a large proportion of the population is vaccinated), the risk of direct harm that one poses to others is low. When there is herd immunity, the chances that one will become infected is lower than when there is no herd immunity. This risk becomes smaller if the unvaccinated individual limits social interaction and wears a mask. And in the event that one does become infected, others around them will be vaccinated and unlikely to contract the virus or become seriously ill themselves. This risk can be further mitigated by requiring those who are infected to quarantine.

When there is herd immunity, the risk of indirect harm posed to others is also small. Vaccination and the quest for herd immunity takes the form of what is known as a collective action problem. Collective action problems emerge when the efforts of most members of a group are needed to produce a common good, but where a failure on the part of some members to contribute will not affect the production of that good. This sets the stage for the possibility of free riding – that is, of gaining from the efforts of others (in this case, enjoying herd immunity) without bearing any of the burdens of its production (through vaccinating). In the case of vaccination, if everyone else is vaccinated, any one individual who refrains from vaccinating will not frustrate the efforts to achieve herd immunity.

Thus, when a sufficient number of persons are vaccinated, the risk of direct or indirect harm that an unvaccinated individual poses to others is relatively small.

We have not yet, however, achieved herd immunity against coronavirus. (Some have suggested that, since vaccines against COVID-19 do not provide 100% protection against infection, herd immunity in the case of COVID-19 may be very difficult, if not impossible to achieve.)

When there is no herd immunity, the risk of direct harm that an unvaccinated individual poses to others is higher than where is herd immunity. In most cases, the risk of direct harm that an unvaccinated individual poses to others is also likely higher risk than that posed by a vaccinated individual. However, given that it is possible for vaccinated individuals to contract and spread the illness through so-called breakthrough infections, by how much is not clear. Add to this certain risk-mitigating behaviours that an individual can adopt – again, by limiting social interaction, wearing a mask, and staying home when ill – and the risk of direct harm to others decreases. In short, while there may be a higher risk of harm to others posed by the unvaccinated, this harm is not immediate, and there are mitigating measures one can take to reduce this risk of harm.

Where there is no herd immunity, a single individual’s choice to become vaccinated would likely not be sufficient to achieve herd immunity. Thus, in this case, there is no clear benefit to others by her becoming vaccinated. And no one is much worse off by her refraining from vaccinating, since there is no herd immunity in the population to begin with. Thus, whether one vaccinates or not where there is no herd immunity makes no significant difference to the degree of indirect harm prevented or produced.

Thus, even where there is no herd immunity, it is not obvious that the unvaccinated pose a high enough risk of harm to others to warrant overriding bodily autonomy.

There is an interesting paradox here. Each individual’s actions alone—in this case, one’s refusal to become vaccinated—are not sufficient to cause much (if any) harm to others. But the combined refusals of many is sufficient to cause harm. However, if we accept that the only justifiable interference with individual liberty is to protect others from harm and accept that each individual’s refusal to become vaccinated—taken in isolation—does not pose a significant risk of harm, an appeal to harm is not sufficient to override individual liberty. The case for protecting others from harm through vaccine mandates is weak.


There are good prudential reasons to become vaccinated. It is clear that vaccination dramatically reduces the risk of serious illness from COVID-19. And there may be additional moral reasons why one should be vaccinated. One might, for example appeal to considerations of fairness—that is, that everyone should contribute their fair share of the collective effort (in this case, by becoming vaccinated) to produce herd immunity.

But not all moral obligations are enforceable by the state. And given the presumptive case against interference with individual bodily autonomy, a very strong justification needs to be provided for why that autonomy should be set aside. I have here followed Mill in his contention that the only justifiable interference with an individual’s liberty is to protect others from harm. However, given the relatively low level of harm that any one individual poses to others, directly and indirectly, both where there is herd immunity and where there is not, an appeal to the harm principle will not suffice to set aside liberty in the case of vaccination against COVID-19.

Unfortunately, it may turn out (as we are seeing in many places) that not enough people will become vaccinated and public health will suffer. But so long as vaccination is treated as a medical decision and governed by an autonomy-based ethics (as arguably it should), it is hard to see how the goals of public health can be reconciled with the liberty of the individual. .