Doc feature in README

README.md

@@ -85,6 +85,33 @@ TWILIO_AUTH_TOKEN # Token from your Twilio account
 SMS_SENDER # Twilio's phone number. You need to purchase one there with SMS capability.
 ```
 
+### Track delegated votes and unvotes
+
+Votes and revocations done on behalf of other members are tracked through the
+`versions` table using `PaperTrail`. This enables fetching a log of actions
+involving a particular delegation or consultation for auditing purposes. This
+keeps out regular votes and unvotes.
+
+When performing votes and unvotes of delegations you'll see things like the
+following in your `versions` table:
+
+```sql
+  id  |          item_type           | item_id |  event  | whodunnit | decidim_action_delegator_delegation_id 
+------+------------------------------+---------+---------+-----------+----------------------------------------
+ 2019 | Decidim::Consultations::Vote |     143 | destroy | 1         |                                     22
+ 2018 | Decidim::Consultations::Vote |     143 | create  | 1         |                                     22
+ 2017 | Decidim::Consultations::Vote |     142 | create  | 1         |                                     23
+ 2016 | Decidim::Consultations::Vote |     138 | destroy | 1         |                                     23
+```
+
+Note that the `item_type` is `Decidim::Consultations::Vote` and `whoddunit`
+refers to a `Decidim::User` record. This enables joining `versions` and
+`decidim_users` tables although this doesn't follow Decidim's convention of
+using gids, such as `gid://decidim/Decidim::User/1`.
+
+You can use `Decidim::ActionDelegato::DelegatedVotes::Versions` query object for
+that matter.
+
 ## Contributing
 
 See [Decidim](https://github.com/decidim/decidim).