In a white paper published by the American Civil Liberties Union, the watchdog agency warns that apps mean to track the spread of COVID-19 could come with major privacy risks.

While the ACLU doesn't expressly oppose apps that use data from people's phones to trace the spread of the virus, the organization says in its advisory that implementation will require a greater level of consent from users - especially when it comes to how their data is shared.

The ACLU says contact tracing apps could carry 'significant' privacy risks if they're not designed with robust controls on safety and consent (stock)

'While some of these systems could offer public health benefits, they may also cause significant risks to privacy, civil rights, and civil liberties,' writes ACLU’s Surveillance and Cybersecurity Counsel, Jennifer Stisa Granick in a blog post.

'If such systems are to work, there must be widespread, free, and quick testing available.'

The ACLU warns 'voluntariness' should be an integral part of any contact tracing system, otherwise users may reject its implementation entirely by disabling their location data.

'The systems must also be widely adopted, but that will not happen if people do not trust them. For there to be trust, the tool must protect privacy, be voluntary, and store data on an individual’s device rather than in a centralized repository,' wrote the ACLU.

According to the organization, contact tracing proposals like those recently set forth jointly by Google and Apple should also have express conditions on how the data can be used.

For instance, a statute dictating that any data collected won't be used for advertising purposes in addition to limits on how long the data can be retained by governments.

An NHS contact tracing app would only completely stop the spread of coronavirus if 80 per cent of current smartphone owners use it, researchers have warned

The ACLU has also questioned whether data could be used for surveillance purposes and has sent a Freedom of Information Act request to the Department of Health and Human Services (HHS) and Centers for Disease Control (CDC) for correspondences with the Google and Apple.

The ACLU's guidance on contact tracing comes on the heels of an initiative by Google and Apple who partnered up to provide governments and health authorities with support on developing their own contact tracing apps.

Specifically, the companies are providing governments and health agencies access to their application programming interfaces (APIs) so that they can interface with Google and Apple's data banks to build out their own contact tracing apps.