What plausible deniability means
Plausible deniability is a security property that lets someone credibly deny possessing certain encrypted data or authoring a message because the available evidence does not prove a single explanation. It does not make coercion harmless or erase every trace.
The coercion threat model
End-to-end encryption protects data in transit, but it does not by itself protect an unlocked device. Plausible-deniability features aim to reduce the evidence available during physical access; they cannot make coercion safe.
Secondary identities and expellable passphrases
Layergram can keep secondary cryptographic identities isolated behind a secret passphrase. Expelling an identity removes its active material from memory; the result still depends on the operating system, storage, and device state.
The deleted-key explanation
If the keys for an old identity have been removed, Layergram may no longer be able to decrypt its messages. A signature-less payload can make authorship harder to prove from the payload alone, but surrounding evidence may still link it to a person.
Encrypted local metadata
Layergram encrypts stored message IDs and timestamps in its local database. This limits straightforward inspection without the key, but device artifacts, operating-system data, or the transport app may still reveal timing and relationships.
Ephemeral transport can reduce retention
Layergram can be paired with disappearing messages and Delete after read to reduce retained ciphertext. Transport providers and devices control their own copies and retention, so deletion cannot be guaranteed outside Layergram.
Message repudiation
Layergram does not add a standalone digital signature intended to prove authorship to third parties. This reduces durable cryptographic attribution from the payload alone; it does not make sender identification impossible.
What it does not guarantee
Plausible deniability is not invisibility and cannot guarantee safety under coercion. An unlocked or compromised device, copies in a transport app, screenshots, backups, or other evidence can still reveal a conversation. Layergram can reduce some traces, but it cannot control the operating system, transport apps, or a physical adversary.
Plausible deniability: common questions
Is plausible deniability the same as encryption?
No. Encryption protects message content from readers who do not have the key. Plausible deniability addresses whether available evidence can conclusively prove that particular encrypted data exists or that a specific person authored a message.
Can plausible deniability protect an unlocked or compromised device?
Not by itself. Device state, screenshots, backups, transport-app history, operating-system telemetry, and human behavior can all provide evidence outside the cryptographic protocol.
How does Layergram apply plausible deniability?
Layergram separates local cryptographic identities, lets a user expel a secondary identity from memory, encrypts locally stored metadata, and uses payloads designed to reduce conclusive attribution. The result still depends on device security and operational context.