The Department of Justice today published an open letter to Facebook from international law enforcement partners from the United States, United Kingdom, and Australia in response to the company’s publicly announced plans to implement end-to-end-encryption across its messaging services.

The letter is signed by Attorney General William P. Barr, United Kingdom Home Secretary Priti Patel, Australia’s Minister for Home Affairs Peter Dutton, and Acting Homeland Security Secretary Kevin McAleenan.

Addressed to Facebook’s CEO, Mark Zuckerberg, the letter requests that Facebook not proceed with its end-to-end encryption plan without ensuring there will be no reduction in the safety of Facebook users and others, and without providing law enforcement court-authorized access to the content of communications to protect the public, particularly child users.

Facebook’s proposals would put at risk its own vital work that keeps children safe. In 2018, Facebook made 16.8 million reports of child sexual exploitation and abuse content to the National Center for Missing & Exploited Children (NCMEC), 12 million of which it is estimated would be lost if the company pursues its plan to implement end-to-end encryption.

The concerns highlighted in this letter to Facebook are at the core of the Department of Justice’s Lawful Access Summit that will take place on Friday, Oct. 4, 2019, on warrant-proof encryption and its impact on child exploitation cases.

The summit will feature a keynote address by Attorney General Barr along with remarks by Deputy Attorney General Jeffrey A. Rosen, FBI Director Christopher Wray, and NCMEC co-founder John Walsh. The summit also includes a dialogue with Australian Minister Dutton and U.K. Home Secretary Patel, who will discuss international perspectives on the area of encryption and why Facebook must reconsider its plan to implement end-to-end encryption.

Use of end-to-end encryption, which allows messages to be decrypted only by end users, leaves service providers unable to produce readable content in response to wiretap orders and search warrants. This barrier allows criminals to avoid apprehension by law enforcement by limiting access to crucial evidence in the form of encrypted digital communications. The use of end-to-end encryption and other highly sophisticated encryption technologies significantly hinders, or entirely prevents serious criminal and national security investigations.

Many service providers, device manufacturers, and application developers who use encryption fail to implement technology that would allow the government to obtain electronic evidence necessary to investigate and prosecute threats to public safety and national security. Law enforcement believes it is crucial for technology companies to include lawful access mechanisms in the design of their products or services. The Department of Justice is committed to developing a coherent national and international policy that encourages responsible encryption, enhances public safety, while protecting privacy and cybersecurity.