Reddit is updating its privacy policy to prohibit posting nude and sexual images without the consent of the subject.

The change, which will go into effect March 10, is a departure for the sprawling online community, which has avoided policing non-consensual explicit content.

It's only a first step, but for activists who have been pushing to get revenge porn taken seriously by tech companies and lawmakers, it's an important victory.

Limits of the law

If you find a nude photo of yourself online, say one taken without your knowledge, stolen from your smartphone or texted to an ex in private, your options are limited.

Only a few states have passed revenge porn laws, and they're largely ineffective against a site like Reddit, which is protected by section 230 of the federal Communications Decency Act. The act gives platforms such as Facebook (FB), Twitter (TWTR) and Reddit immunity when third parties post anything that doesn't violate federal law.

California 'revenge porn' law may miss some victims

That's why activists have been pushing for a federal revenge porn law. California Rep. Jackie Speier is leading efforts to craft such legislation. And even if legislation isn't the best solution, the threat of federal interference could motivate more sites to crack down.

"If tech platforms wanted to step up and tackle this issue, they could do so much more than laws to eradicate this issue over time," said Mary Anne Franks, a law professor at Miami Law School and vice president of the Cyber Civil Rights Initiative, an anti revenge porn advocacy group.

Tech companies have more resources and expertise than the government to come up with innovative solutions. They could work together on fixes, like they have for suicide prevention and child exploitation. For example, a shared database of flagged images could prevent the same photo from reappearing on other sites.

How Reddit's plan works

Reddit's enforcement plan is low tech.

The policy update says members cannot post or link to unauthorized images and videos of people who are nude or engaged in a sexual act.

If a woman finds a nude image of herself, she must email Reddit and ask that it be taken down. The policy puts the burden of proof on the victim, and the same image could still pop up elsewhere on the site or the Internet.

"We can't ask that every post prove consent as it would not be sustainable or even very effective," explained Jessica Moreno, Reddit's head of community.

Moderators are getting additional training, though Moreno says many are already actively removing unauthorized images upon request, or when something is "obviously posted without consent."

"It does put the burden on the victim but honestly, compared to how things were before, this is still really good," said Franks.

Changing the tech industry

Further industry-wide change will require a shift in how companies think about nude and sexual images.

Most have policies about removing private data such as social security numbers and addresses, but they don't always apply the same strict standards to photos.

Feds take down revenge porn king

Last year's major hack of celebrity photos was a turning point. Scores of stolen images were posted on Reddit, and the company was criticized for being slow to remove them. Even after one of the communities was shut down, the CEO of Reddit at the time -- Yishan Wong -- said there was no plan to change policy.

"We will try not to interfere -- not because we don't care, but because we care that you make your choices between right and wrong," Wong said in a blog post.

Then Wong resigned abruptly, Ellen Pao was brought on board as interim CEO, and Reddit had a change of heart. In a blog post announcing the update, Reddit said, "Last year, we missed a chance to be a leader in social media."

"This was something we decided on as a team, because we know how important user privacy has always been to the Reddit userbase," said Moreno.

Whether it's a heartfelt change in culture, fear of being criminally liable in the future, or a savvy business move to help it grow beyond its current 9,000 communities, Reddit's small privacy update is a big deal.

Now the spotlight is on other tech companies to take a similar stand.