diff --git a/lib/clearance/back_door.rb b/lib/clearance/back_door.rb
index f9e62c983..58fe82d65 100644
--- a/lib/clearance/back_door.rb
+++ b/lib/clearance/back_door.rb
@@ -54,7 +54,6 @@ def sign_in_through_the_back_door(env)
       if user_param.present?
         query_string = Rack::Utils.build_query(params)
         env[Rack::QUERY_STRING] = query_string
-        env[Rack::RACK_REQUEST_QUERY_STRING] = query_string
         user = find_user(user_param)
         env[:clearance].sign_in(user)
       end
diff --git a/spec/dummy/app/controllers/application_controller.rb b/spec/dummy/app/controllers/application_controller.rb
index c7635bbb6..c88fb42a4 100644
--- a/spec/dummy/app/controllers/application_controller.rb
+++ b/spec/dummy/app/controllers/application_controller.rb
@@ -2,6 +2,6 @@ class ApplicationController < ActionController::Base
   include Clearance::Controller
 
   def show
-    render inline: "Hello user #<%= current_user.id %>", layout: false
+    render inline: "Hello user #<%= current_user.id %> #{params.to_json}", layout: false
   end
 end
diff --git a/spec/requests/backdoor_spec.rb b/spec/requests/backdoor_spec.rb
index 75887291e..bec2b5571 100644
--- a/spec/requests/backdoor_spec.rb
+++ b/spec/requests/backdoor_spec.rb
@@ -8,4 +8,12 @@
 
     expect(cookies["remember_token"]).to eq user.remember_token
   end
+
+  it "removes the `as` param but leaves other parameters unchanged" do
+    user = create(:user)
+
+    get root_path(as: user.to_param, foo: 'bar')
+
+    expect(response.body).to include('{"foo":"bar","controller":"application","action":"show"}')
+  end
 end