Every event on your account is an entry in your proof record. A consent given, a document received, a document viewed and a deletion are all entries. The audit trail is how you read them.
An entry holds its number, the kind of event, references to the people and documents involved, who acted and the exact time. It also holds the SHA-256 fingerprint of the entry before it. Its own fingerprint is worked out from all of that.
A fingerprint covers the one before it. So changing an entry changes its fingerprint, and the next entry no longer matches it. The mismatch runs on through every entry after. An entry removed or added in the middle breaks the match in the same way.
Nobody edits or deletes an entry. The app has no way to do it. A correction is a new entry. Your account's entries also link to your account's own previous entry. That link lets you check your export on its own.
Entries hold references and fingerprints. They never hold your client's name, phone, email or files. A few carry words your firm typed, such as the reason for declining a request or the law you named. Names and request titles are read from your account when you open a page. That is why a deletion leaves proof behind. The entry that records a deletion outlives the data it points to.
We check the whole chain automatically every night. Once a day we also copy its latest fingerprint to storage that cannot be rewritten, as daily anchors.
The chain is what lets you show a client or an auditor what was recorded and when. It shows the record has not changed since. You can check it yourself from the evidence export.