In humans as well as other animals, displays of body strength such as power postures or deep masculine voices are associated with prevalence in conflicts of interest and facilitated access to resources. We conduct here an ecological and highly critical test of this hypothesis in a domain that, on first thought, would appear to be shielded from such influences: access to emergency medical care. Using acoustic manipulations of vocal masculinity, we systematically varied the perceived level of physical dominance of mock patients calling a medical call center simulator. Callers whose voice were perceived as indicative of physical dominance (i.e. those with low fundamental and formant frequency voices) obtained a higher grade of response, a higher evaluation of medical emergency and longer attention from physicians than callers with strictly identical medical needs whose voice signaled lower physical dominance. Strikingly, while the effect was important for physician participants, it was virtually non-existent when calls were processed by non-medically-trained phone operators. This finding demonstrates an unprecedented degree of vulnerability of telephone-based medical decisions to extra-medical factors carried by vocal cues, and shows that it may not simply be assumed that more medical training will shield decisions from such influences.