Facebook could impose new limits on who can live stream to Facebook Live following the Christchurch terror attack, which was broadcast live on the social network.

In an open letter published in the New Zealand Herald, Facebook COO Sheryl Sandberg laid out steps the company is taking to change its policies following criticism after the Christchurch terrorist attack. Among them: new rules on who is allowed to use Facebook Live.

"We are exploring restrictions on who can go Live depending on factors such as prior Community Standard violations," Sandberg wrote.

The proposal was light on details. Sandberg didn't elaborate on exactly how Facebook might restrict the ability to live stream, other than suggesting that those who have broken the company's rules in the past may be affected.

Still, the fact that Facebook is even exploring restrictions to Facebook Live suggests that global criticism is having an effect. Many people have said the company needs to rein in its live streaming feature following the Christchurch shooting, in which the shooter broadcast a 17-minute live video of his attack.

Facebook later said it didn't receive its first report until 12 minutes later -- and that the original live stream was watched more than 4,000 times before it was removed.

The video was also shared to other websites, and later re-uploaded to the social network more than 1.5 million times, according to Facebook. Though the company was able to successfully block many of those copies from being shared, portions of the video were widely distributed online in the immediate aftermath of the attacks, despite pleas from police not to do so.

But until we know what changes Facebook might implement and how it will enforce them, it's impossible to say just how effective any policy changes could be.

Sandberg did provide some detail on other ways the company is making changes. She noted that Facebook just announced that it will ban white nationalism and white separatism, and use its AI technology to help enforce the ban. This change will apply to several New Zealand-specific groups, Sandberg said, including the Lads Society, the United Patriots Front, the Antipodean Resistance, and National Front New Zealand.

Facebook will also be "providing support" to local mental health organizations in the country, Sandberg said.