No embed is send when a user gets "auto-unwatched" after a ban
When we ban a user that's currently being watched, they are automatically unwatched and Python is supposed to send an embed notifying us of that to the relevant watch channel. See [line 141 of the BigBrother cog](https://github.com/python-discord/bot/blob/master/bot/cogs/bigbrother.py#L141).

However, at the moment, no such embed is being send, although I do think the user is getting unwatched. We should probably look into that and fix it. While we're at it, we may want to consider adding an unwatch note to the user as well, just like we do when we unwatch someone manually.

At the moment, I don't know what's causing the bug. A quick review of the code revealed nothing obvious.
diff --git a/bot/cogs/moderation/infractions.py b/bot/cogs/moderation/infractions.py
index 9ea17b2b..efa19f59 100644
--- a/bot/cogs/moderation/infractions.py
+++ b/bot/cogs/moderation/infractions.py
@@ -67,7 +67,7 @@ class Infractions(InfractionScheduler, commands.Cog):
 
     @command()
     async def ban(self, ctx: Context, user: FetchedMember, *, reason: str = None) -> None:
-        """Permanently ban a user for the given reason."""
+        """Permanently ban a user for the given reason and stop watching them with Big Brother."""
         await self.apply_ban(ctx, user, reason)
 
     # endregion
@@ -230,7 +230,11 @@ class Infractions(InfractionScheduler, commands.Cog):
 
     @respect_role_hierarchy()
     async def apply_ban(self, ctx: Context, user: UserSnowflake, reason: str, **kwargs) -> None:
-        """Apply a ban infraction with kwargs passed to `post_infraction`."""
+        """
+        Apply a ban infraction with kwargs passed to `post_infraction`.
+
+        Will also remove the banned user from the Big Brother watch list if applicable.
+        """
         if await utils.has_active_infraction(ctx, user, "ban"):
             return
 
@@ -243,6 +247,20 @@ class Infractions(InfractionScheduler, commands.Cog):
         action = ctx.guild.ban(user, reason=reason, delete_message_days=0)
         await self.apply_infraction(ctx, infraction, user, action)
 
+        if infraction.get('expires_at') is not None:
+            log.trace(f"Ban isn't permanent; user {user} won't be unwatched by Big Brother.")
+            return
+
+        bb_cog = self.bot.get_cog("Big Brother")
+        if not bb_cog:
+            log.error(f"Big Brother cog not loaded; perma-banned user {user} won't be unwatched.")
+            return
+
+        log.trace(f"Big Brother cog loaded; attempting to unwatch perma-banned user {user}.")
+
+        bb_reason = "User has been permanently banned from the server. Automatically removed."
+        await bb_cog.apply_unwatch(ctx, user, bb_reason, send_message=False)
+
     # endregion
     # region: Base pardon functions
 
diff --git a/bot/cogs/verification.py b/bot/cogs/verification.py
index 57b50c34..107bc105 100644
--- a/bot/cogs/verification.py
+++ b/bot/cogs/verification.py
@@ -6,13 +6,9 @@ from discord import Colour, Forbidden, Message, NotFound, Object
 from discord.ext import tasks
 from discord.ext.commands import Cog, Context, command
 
+from bot import constants
 from bot.bot import Bot
 from bot.cogs.moderation import ModLog
-from bot.constants import (
-    Bot as BotConfig,
-    Channels, Colours, Event,
-    Filter, Icons, MODERATION_ROLES, Roles
-)
 from bot.decorators import InChannelCheckFailure, in_channel, without_role
 from bot.utils.checks import without_role_check
 
@@ -29,18 +25,23 @@ your information removed here as well.
 
 Feel free to review them at any point!
 
-Additionally, if you'd like to receive notifications for the announcements we post in <#{Channels.announcements}> \\
-from time to time, you can send `!subscribe` to <#{Channels.bot_commands}> at any time to assign yourself the \\
-**Announcements** role. We'll mention this role every time we make an announcement.
+Additionally, if you'd like to receive notifications for the announcements \\
+we post in <#{constants.Channels.announcements}>
+from time to time, you can send `!subscribe` to <#{constants.Channels.bot_commands}> at any time \\
+to assign yourself the **Announcements** role. We'll mention this role every time we make an announcement.
 
 If you'd like to unsubscribe from the announcement notifications, simply send `!unsubscribe` to \\
-<#{Channels.bot_commands}>.
+<#{constants.Channels.bot_commands}>.
 """
 
-PERIODIC_PING = (
-    f"@everyone To verify that you have read our rules, please type `{BotConfig.prefix}accept`."
-    f" If you encounter any problems during the verification process, ping the <@&{Roles.admins}> role in this channel."
-)
+if constants.DEBUG_MODE:
+    PERIODIC_PING = "Periodic checkpoint message successfully sent."
+else:
+    PERIODIC_PING = (
+        f"@everyone To verify that you have read our rules, please type `{constants.Bot.prefix}accept`."
+        " If you encounter any problems during the verification process, "
+        f"ping the <@&{constants.Roles.admins}> role in this channel."
+    )
 BOT_MESSAGE_DELETE_DELAY = 10
 
 
@@ -59,7 +60,7 @@ class Verification(Cog):
     @Cog.listener()
     async def on_message(self, message: Message) -> None:
         """Check new message event for messages to the checkpoint channel & process."""
-        if message.channel.id != Channels.verification:
+        if message.channel.id != constants.Channels.verification:
             return  # Only listen for #checkpoint messages
 
         if message.author.bot:
@@ -85,20 +86,20 @@ class Verification(Cog):
 
             # Send pretty mod log embed to mod-alerts
             await self.mod_log.send_log_message(
-                icon_url=Icons.filtering,
-                colour=Colour(Colours.soft_red),
+                icon_url=constants.Icons.filtering,
+                colour=Colour(constants.Colours.soft_red),
                 title=f"User/Role mentioned in {message.channel.name}",
                 text=embed_text,
                 thumbnail=message.author.avatar_url_as(static_format="png"),
-                channel_id=Channels.mod_alerts,
-                ping_everyone=Filter.ping_everyone,
+                channel_id=constants.Channels.mod_alerts,
+                ping_everyone=constants.Filter.ping_everyone,
             )
 
-        ctx: Context = await self.bot.get_context(message)
+        ctx: Context = await self.get_context(message)
         if ctx.command is not None and ctx.command.name == "accept":
             return
 
-        if any(r.id == Roles.verified for r in ctx.author.roles):
+        if any(r.id == constants.Roles.verified for r in ctx.author.roles):
             log.info(
                 f"{ctx.author} posted '{ctx.message.content}' "
                 "in the verification channel, but is already verified."
@@ -120,12 +121,12 @@ class Verification(Cog):
             await ctx.message.delete()
 
     @command(name='accept', aliases=('verify', 'verified', 'accepted'), hidden=True)
-    @without_role(Roles.verified)
-    @in_channel(Channels.verification)
+    @without_role(constants.Roles.verified)
+    @in_channel(constants.Channels.verification)
     async def accept_command(self, ctx: Context, *_) -> None:  # We don't actually care about the args
         """Accept our rules and gain access to the rest of the server."""
         log.debug(f"{ctx.author} called !accept. Assigning the 'Developer' role.")
-        await ctx.author.add_roles(Object(Roles.verified), reason="Accepted the rules")
+        await ctx.author.add_roles(Object(constants.Roles.verified), reason="Accepted the rules")
         try:
             await ctx.author.send(WELCOME_MESSAGE)
         except Forbidden:
@@ -133,17 +134,17 @@ class Verification(Cog):
         finally:
             log.trace(f"Deleting accept message by {ctx.author}.")
             with suppress(NotFound):
-                self.mod_log.ignore(Event.message_delete, ctx.message.id)
+                self.mod_log.ignore(constants.Event.message_delete, ctx.message.id)
                 await ctx.message.delete()
 
     @command(name='subscribe')
-    @in_channel(Channels.bot_commands)
+    @in_channel(constants.Channels.bot_commands)
     async def subscribe_command(self, ctx: Context, *_) -> None:  # We don't actually care about the args
         """Subscribe to announcement notifications by assigning yourself the role."""
         has_role = False
 
         for role in ctx.author.roles:
-            if role.id == Roles.announcements:
+            if role.id == constants.Roles.announcements:
                 has_role = True
                 break
 
@@ -152,22 +153,22 @@ class Verification(Cog):
             return
 
         log.debug(f"{ctx.author} called !subscribe. Assigning the 'Announcements' role.")
-        await ctx.author.add_roles(Object(Roles.announcements), reason="Subscribed to announcements")
+        await ctx.author.add_roles(Object(constants.Roles.announcements), reason="Subscribed to announcements")
 
         log.trace(f"Deleting the message posted by {ctx.author}.")
 
         await ctx.send(
-            f"{ctx.author.mention} Subscribed to <#{Channels.announcements}> notifications.",
+            f"{ctx.author.mention} Subscribed to <#{constants.Channels.announcements}> notifications.",
         )
 
     @command(name='unsubscribe')
-    @in_channel(Channels.bot_commands)
+    @in_channel(constants.Channels.bot_commands)
     async def unsubscribe_command(self, ctx: Context, *_) -> None:  # We don't actually care about the args
         """Unsubscribe from announcement notifications by removing the role from yourself."""
         has_role = False
 
         for role in ctx.author.roles:
-            if role.id == Roles.announcements:
+            if role.id == constants.Roles.announcements:
                 has_role = True
                 break
 
@@ -176,12 +177,12 @@ class Verification(Cog):
             return
 
         log.debug(f"{ctx.author} called !unsubscribe. Removing the 'Announcements' role.")
-        await ctx.author.remove_roles(Object(Roles.announcements), reason="Unsubscribed from announcements")
+        await ctx.author.remove_roles(Object(constants.Roles.announcements), reason="Unsubscribed from announcements")
 
         log.trace(f"Deleting the message posted by {ctx.author}.")
 
         await ctx.send(
-            f"{ctx.author.mention} Unsubscribed from <#{Channels.announcements}> notifications."
+            f"{ctx.author.mention} Unsubscribed from <#{constants.Channels.announcements}> notifications."
         )
 
     # This cannot be static (must have a __func__ attribute).
@@ -193,7 +194,7 @@ class Verification(Cog):
     @staticmethod
     def bot_check(ctx: Context) -> bool:
         """Block any command within the verification channel that is not !accept."""
-        if ctx.channel.id == Channels.verification and without_role_check(ctx, *MODERATION_ROLES):
+        if ctx.channel.id == constants.Channels.verification and without_role_check(ctx, *constants.MODERATION_ROLES):
             return ctx.command.name == "accept"
         else:
             return True
@@ -201,7 +202,7 @@ class Verification(Cog):
     @tasks.loop(hours=12)
     async def periodic_ping(self) -> None:
         """Every week, mention @everyone to remind them to verify."""
-        messages = self.bot.get_channel(Channels.verification).history(limit=10)
+        messages = self.bot.get_channel(constants.Channels.verification).history(limit=10)
         need_to_post = True  # True if a new message needs to be sent.
 
         async for message in messages:
@@ -215,7 +216,7 @@ class Verification(Cog):
                 break
 
         if need_to_post:
-            await self.bot.get_channel(Channels.verification).send(PERIODIC_PING)
+            await self.bot.get_channel(constants.Channels.verification).send(PERIODIC_PING)
 
     @periodic_ping.before_loop
     async def before_ping(self) -> None:
diff --git a/bot/cogs/watchchannels/bigbrother.py b/bot/cogs/watchchannels/bigbrother.py
index c601e0d4..903c87f8 100644
--- a/bot/cogs/watchchannels/bigbrother.py
+++ b/bot/cogs/watchchannels/bigbrother.py
@@ -52,6 +52,21 @@ class BigBrother(WatchChannel, Cog, name="Big Brother"):
         A `reason` for adding the user to Big Brother is required and will be displayed
         in the header when relaying messages of this user to the watchchannel.
         """
+        await self.apply_watch(ctx, user, reason)
+
+    @bigbrother_group.command(name='unwatch', aliases=('uw',))
+    @with_role(*MODERATION_ROLES)
+    async def unwatch_command(self, ctx: Context, user: FetchedMember, *, reason: str) -> None:
+        """Stop relaying messages by the given `user`."""
+        await self.apply_unwatch(ctx, user, reason)
+
+    async def apply_watch(self, ctx: Context, user: FetchedMember, reason: str) -> None:
+        """
+        Add `user` to watched users and apply a watch infraction with `reason`.
+
+        A message indicating the result of the operation is sent to `ctx`.
+        The message will include `user`'s previous watch infraction history, if it exists.
+        """
         if user.bot:
             await ctx.send(f":x: I'm sorry {ctx.author}, I'm afraid I can't do that. I only watch humans.")
             return
@@ -90,10 +105,13 @@ class BigBrother(WatchChannel, Cog, name="Big Brother"):
 
         await ctx.send(msg)
 
-    @bigbrother_group.command(name='unwatch', aliases=('uw',))
-    @with_role(*MODERATION_ROLES)
-    async def unwatch_command(self, ctx: Context, user: FetchedMember, *, reason: str) -> None:
-        """Stop relaying messages by the given `user`."""
+    async def apply_unwatch(self, ctx: Context, user: FetchedMember, reason: str, send_message: bool = True) -> None:
+        """
+        Remove `user` from watched users and mark their infraction as inactive with `reason`.
+
+        If `send_message` is True, a message indicating the result of the operation is sent to
+        `ctx`.
+        """
         active_watches = await self.bot.api_client.get(
             self.api_endpoint,
             params=ChainMap(
@@ -102,6 +120,7 @@ class BigBrother(WatchChannel, Cog, name="Big Brother"):
             )
         )
         if active_watches:
+            log.trace("Active watches for user found.  Attempting to remove.")
             [infraction] = active_watches
 
             await self.bot.api_client.patch(
@@ -111,8 +130,20 @@ class BigBrother(WatchChannel, Cog, name="Big Brother"):
 
             await post_infraction(ctx, user, 'watch', f"Unwatched: {reason}", hidden=True, active=False)
 
-            await ctx.send(f":white_check_mark: Messages sent by {user} will no longer be relayed.")
-
             self._remove_user(user.id)
+
+            if not send_message:  # Prevents a message being sent to the channel if part of a permanent ban
+                log.debug(f"Perma-banned user {user} was unwatched.")
+                return
+            log.trace("User is not banned.  Sending message to channel")
+            message = f":white_check_mark: Messages sent by {user} will no longer be relayed."
+
         else:
-            await ctx.send(":x: The specified user is currently not being watched.")
+            log.trace("No active watches found for user.")
+            if not send_message:  # Prevents a message being sent to the channel if part of a permanent ban
+                log.debug(f"{user} was not on the watch list; no removal necessary.")
+                return
+            log.trace("User is not perma banned. Send the error message.")
+            message = ":x: The specified user is currently not being watched."
+
+        await ctx.send(message)
['bot/cogs/verification.py', 'bot/cogs/moderation/infractions.py', 'bot/cogs/watchchannels/bigbrother.py']