Every moderator knows the pattern: you ban someone, and they're back an hour later with a new account. Sock puppets agree with each other, brigades arrive from nowhere, and AI accounts now post convincingly human replies. Proof of personhood gives communities a way to know each account is a different real person, without asking members to give up their anonymity.
The problems it solves
- Ban evasion. A ban that applies to an account is easy to dodge. A ban that applies to a person sticks.
- Sock puppets and brigading. One person with many accounts can fake agreement, swing votes and drown out others.
- AI and bot accounts. Each verified account has to be backed by a different real person, so bot farms can't scale.
- Scammers in trading and marketplace communities, who come back under a new name after every report.
Why anonymity still matters
Many communities depend on people being able to post without revealing who they are: support groups, communities about health, sexuality or politics, and anyone who uses a throwaway for sensitive topics. Asking members to upload an ID to moderators would destroy that.
Privacy-preserving proof of personhood separates the two:
- Moderators learn that an account belongs to a verified, unique person.
- Moderators don't learn the person's name, ID or anything else, and the person's other accounts elsewhere stay unlinked.
Ways to use it
You don't have to require verification for everyone. Common patterns:
- A "verified human" badge or flair, optional, that members can choose to earn.
- Verification for abused actions only: posting links, posting in certain flairs or channels, messaging strangers, or joining a vote.
- One verified account per person, so alts can't be verified alongside a main account.
- Bans that follow the person. When a banned person verifies another account, moderators are told, or the account is banned automatically.
- Shared bans between communities that choose to work together, so a troll banned in one isn't welcome in its partners, without revealing which account was banned.
Rolling it out
- Start optional. Offer the badge, explain what it means, and let early adopters lead.
- Explain the privacy. "We learn you're a real, unique person. We never see your ID or learn your name."
- Apply it where abuse is. Require it only for the posts, flairs or actions that attract fakes.
- Measure: repeat bans, reports, and moderator time before and after.
Human Pass for communities
Human Pass offers privacy-preserving proof of personhood with a government ID check done once, after which members simply sign in. A Human Pass app for Reddit communities is in testing, with verified-human flair, one account per person, posting limits for unverified accounts, ban-evasion detection, and bans shared between subreddits that agree to it. Moderators never see members' identities, and a ban is only shared as "the same person is banned there", never which account.