diff --git a/moto/kinesis/models.py b/moto/kinesis/models.py
index d24afd2b7..a68103f26 100644
--- a/moto/kinesis/models.py
+++ b/moto/kinesis/models.py
@@ -203,7 +203,7 @@ class KinesisBackend(BaseBackend):
 
     def create_stream(self, stream_name, shard_count, region):
         if stream_name in self.streams:
-           return ResourceInUseError(stream_name)
+           raise ResourceInUseError(stream_name)
         stream = Stream(stream_name, shard_count, region)
         self.streams[stream_name] = stream
         return stream
diff --git a/moto/kinesis/responses.py b/moto/kinesis/responses.py
index 61a4a8199..dd364c49a 100644
--- a/moto/kinesis/responses.py
+++ b/moto/kinesis/responses.py
@@ -25,9 +25,7 @@ class KinesisResponse(BaseResponse):
     def create_stream(self):
         stream_name = self.parameters.get('StreamName')
         shard_count = self.parameters.get('ShardCount')
-        stream = self.kinesis_backend.create_stream(stream_name, shard_count, self.region)
-        if isinstance(stream, BadRequest):
-              return stream.description
+        self.kinesis_backend.create_stream(stream_name, shard_count, self.region)
         return ""
 
     def describe_stream(self):