A new white paper released by the ACLU cautions again using fever-scanning cameras and infrared temperature-sensing guns to screen people for possible coronavirus symptoms because they are intrusive, ineffective and often inaccurate.

An accompanying NYT article covers the main points of the paper, including the ACLU’s position that these tools can give people a false sense of security, potentially leading them to be less vigilant about health measures like wearing masks or social distancing. The report also warns that pushing for widespread temperature scans during the pandemic could usher in permanent new forms of surveillance and social control.

In terms of effectiveness, fever detection alone is not sufficient to identify SARS-Cov-2 infection, and existing fever scanners – including tympanic thermometers, thermometers guns and standoff thermal cameras – are only reasonably accurate when administered by a trained health professional. The FDA cautions against the widespread use of these devices because most have not been rigorously or independently tested for accuracy.

The report also discusses important privacy issues that temperature checks raise, including whether and what actions should be taken based on a high reading from a remote temperature device.