diff --git a/mitmproxy/console/flowlist.py b/mitmproxy/console/flowlist.py
index ebba1ea4a..653dfa022 100644
--- a/mitmproxy/console/flowlist.py
+++ b/mitmproxy/console/flowlist.py
@@ -166,7 +166,7 @@ class ConnectionItem(urwid.WidgetWrap):
             self.state.delete_flow(self.flow)
             signals.flowlist_change.send(self)
         elif key == "D":
-            f = self.master.duplicate_flow(self.flow)
+            f = self.master.state.duplicate_flow(self.flow)
             self.master.state.set_focus_flow(f)
             signals.flowlist_change.send(self)
         elif key == "m":
diff --git a/mitmproxy/console/flowview.py b/mitmproxy/console/flowview.py
index 4aa09bd96..0422e72b8 100644
--- a/mitmproxy/console/flowview.py
+++ b/mitmproxy/console/flowview.py
@@ -536,7 +536,7 @@ class FlowView(tabs.Tabs):
                 f.kill(self.master)
             self.state.delete_flow(f)
         elif key == "D":
-            f = self.master.duplicate_flow(self.flow)
+            f = self.master.state.duplicate_flow(self.flow)
             signals.pop_view_state.send(self)
             self.master.view_flow(f)
             signals.status_message.send(message="Duplicated.")
diff --git a/mitmproxy/flow/master.py b/mitmproxy/flow/master.py
index 02e5246fd..3d57c7bde 100644
--- a/mitmproxy/flow/master.py
+++ b/mitmproxy/flow/master.py
@@ -57,15 +57,6 @@ class FlowMaster(controller.Master):
     def start_app(self, host, port):
         self.apps.add(app.mapp, host, port)
 
-    def duplicate_flow(self, f):
-        """
-            Duplicate flow, and insert it into state without triggering any of
-            the normal flow events.
-        """
-        f2 = f.copy()
-        self.state.add_flow(f2)
-        return f2
-
     def create_request(self, method, scheme, host, port, path):
         """
             this method creates a new artificial and minimalist request also adds it to flowlist
diff --git a/mitmproxy/flow/state.py b/mitmproxy/flow/state.py
index cb01f6fed..8c8e75c7c 100644
--- a/mitmproxy/flow/state.py
+++ b/mitmproxy/flow/state.py
@@ -261,6 +261,15 @@ class State:
     def killall(self, master):
         self.flows.kill_all(master)
 
+    def duplicate_flow(self, f):
+        """
+            Duplicate flow, and insert it into state without triggering any of
+            the normal flow events.
+        """
+        f2 = f.copy()
+        self.add_flow(f2)
+        return f2
+
 
 class DummyState:
     flows = ()
diff --git a/mitmproxy/web/app.py b/mitmproxy/web/app.py
index 1aab8e8c8..46bdd9e36 100644
--- a/mitmproxy/web/app.py
+++ b/mitmproxy/web/app.py
@@ -275,7 +275,7 @@ class FlowHandler(RequestHandler):
 class DuplicateFlow(RequestHandler):
 
     def post(self, flow_id):
-        self.master.duplicate_flow(self.flow)
+        self.master.state.duplicate_flow(self.flow)
 
 
 class RevertFlow(RequestHandler):
diff --git a/test/mitmproxy/data/addonscripts/duplicate_flow.py b/test/mitmproxy/data/addonscripts/duplicate_flow.py
index b466423cd..02fb8dcec 100644
--- a/test/mitmproxy/data/addonscripts/duplicate_flow.py
+++ b/test/mitmproxy/data/addonscripts/duplicate_flow.py
@@ -2,5 +2,5 @@ from mitmproxy import ctx
 
 
 def request(flow):
-    f = ctx.master.duplicate_flow(flow)
+    f = ctx.master.state.duplicate_flow(flow)
     ctx.master.replay_request(f, block=True)
diff --git a/test/mitmproxy/test_flow.py b/test/mitmproxy/test_flow.py
index 38d61afe4..90b9b61da 100644
--- a/test/mitmproxy/test_flow.py
+++ b/test/mitmproxy/test_flow.py
@@ -452,17 +452,6 @@ class TestFlowMaster:
         f.live = True
         tutils.raises("live", fm.replay_request, f)
 
-    def test_duplicate_flow(self):
-        s = flow.State()
-        fm = flow.FlowMaster(None, None, s)
-        f = tutils.tflow(resp=True)
-        fm.load_flow(f)
-        assert s.flow_count() == 1
-        f2 = fm.duplicate_flow(f)
-        assert f2.response
-        assert s.flow_count() == 2
-        assert s.index(f2) == 1
-
     def test_create_flow(self):
         s = flow.State()
         fm = flow.FlowMaster(None, None, s)
diff --git a/test/mitmproxy/test_flow_state.py b/test/mitmproxy/test_flow_state.py
new file mode 100644
index 000000000..cc05537d6
--- /dev/null
+++ b/test/mitmproxy/test_flow_state.py
@@ -0,0 +1,15 @@
+from mitmproxy import flow
+from . import tutils
+
+
+class TestState:
+    def test_duplicate_flow(self):
+        s = flow.State()
+        fm = flow.FlowMaster(None, None, s)
+        f = tutils.tflow(resp=True)
+        fm.load_flow(f)
+        assert s.flow_count() == 1
+        f2 = fm.state.duplicate_flow(f)
+        assert f2.response
+        assert s.flow_count() == 2
+        assert s.index(f2) == 1