diff --git a/litecord/blueprints/checks.py b/litecord/blueprints/checks.py
index 9c9253a..a27fcb4 100644
--- a/litecord/blueprints/checks.py
+++ b/litecord/blueprints/checks.py
@@ -17,6 +17,8 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
 """
 
+from typing import Union, List
+
 from quart import current_app as app
 
 from litecord.enums import ChannelType, GUILD_CHANS
@@ -53,16 +55,23 @@ async def guild_owner_check(user_id: int, guild_id: int):
         raise Forbidden('You are not the owner of the guild')
 
 
-async def channel_check(user_id, channel_id):
+async def channel_check(user_id, channel_id, *,
+                        only: Union[ChannelType, List[ChannelType]] = None):
     """Check if the current user is authorized
     to read the channel's information."""
     chan_type = await app.storage.get_chan_type(channel_id)
 
     if chan_type is None:
-        raise ChannelNotFound(f'channel type not found')
+        raise ChannelNotFound('channel type not found')
 
     ctype = ChannelType(chan_type)
 
+    if not isinstance(only, list):
+        only = [only]
+
+    if only and ctype not in only:
+        raise ChannelNotFound('invalid channel type')
+
     if ctype in GUILD_CHANS:
         guild_id = await app.db.fetchval("""
         SELECT guild_id
@@ -77,6 +86,9 @@ async def channel_check(user_id, channel_id):
         peer_id = await app.storage.get_dm_peer(channel_id, user_id)
         return ctype, peer_id
 
+    if ctype == ChannelType.GROUP_DM:
+        return ctype
+
 
 async def guild_perm_check(user_id, guild_id, permission: str):
     """Check guild permissions for a user."""
diff --git a/litecord/blueprints/dm_channels.py b/litecord/blueprints/dm_channels.py
index c908e7d..310150b 100644
--- a/litecord/blueprints/dm_channels.py
+++ b/litecord/blueprints/dm_channels.py
@@ -20,6 +20,10 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 from quart import Blueprint, request, current_app as app, jsonify
 from logbook import Logger
 
+from litecord.blueprints.auth import token_check
+from litecord.blueprints.checks import channel_check
+from litecord.enums import ChannelType
+
 log = Logger(__name__)
 bp = Blueprint('dm_channels', __name__)
 
@@ -27,10 +31,17 @@ bp = Blueprint('dm_channels', __name__)
 @bp.route('/<int:dm_chan>/receipients/<int:user_id>', methods=['PUT'])
 async def add_to_group_dm(dm_chan, user_id):
     """Adds a member to a group dm OR creates a group dm."""
-    pass
+    user_id = await token_check()
+    ctype = await channel_check(
+        user_id, dm_chan,
+        only=[ChannelType.DM, ChannelType.GROUP_DM]
+    )
 
 
 @bp.route('/<int:dm_chan>/recipients/<int:user_id>', methods=['DELETE'])
 async def remove_from_group_dm(dm_chan, user_id):
     """Remove users from group dm."""
-    pass
+    user_id = await token_check()
+    ctype = await channel_check(
+        user_id, dm_chan, only=ChannelType.GROUP_DM
+    )