One of the least intrusive disease control measures is the involuntary testing of populations at risk
for communicable disease. The most common example is testing for tuberculosis in high-risk
populations. In voluntary testing has three benefits. First, it allows public health officials to learn
the prevalence of a disease in the community, which is difficult to accomplish with voluntary testing
because of statistical problems associated with self-selected data sets. Second, involuntary
testing identifies infected individuals who may benefit from treatment, and third, it identifies
individuals who may need to be restricted to protect the public health.
Involuntary testing for communicable diseases is legally different from testing for personal
behaviors, such as drug use or the propensity to steal from an employer. The presence or absence
of a communicable disease may be objectively determined and the risk it poses easily quantified.
Since there are no criminal law consequences to the diagnosis of a communicable disease, there
is no need for protections against self- incrimination in disease screening. In many cases treatment
will eradicate the condition. Even when treatment is not possible, only rare circumstances demand
more than minimal workplace restrictions to prevent the spread of the disease. When these
restrictions are required, their sole purpose is to protect others and not to punish the affected
individual. Involuntary testing cannot be used to gather evidence in criminal cases without a proper
search warrant. The U.S. Supreme Court has held that it is unconstitutional to prosecute pregnant
women for endangering their babies when the information about their illegal drug use was collected
through public health testing done with no criminal law due process protections.[Ferguson v City of
Charleston. 532 US 67, 121 SCt 1281, 149 LEd2d 205 (2001)]
