diff --git a/app/models/poll/shift.rb b/app/models/poll/shift.rb
index d64bce9ac..cc5f7045e 100644
--- a/app/models/poll/shift.rb
+++ b/app/models/poll/shift.rb
@@ -6,8 +6,8 @@ class Poll
     validates :booth_id, presence: true
     validates :officer_id, presence: true
     validates :date, presence: true
-    validates :date, uniqueness: { scope: [:officer_id, :booth_id] }
     validates :task, presence: true
+    validates :date, uniqueness: { scope: [:officer_id, :booth_id, :task] }
 
     enum task: { vote_collection: 0, recount_scrutiny: 1 }
 
diff --git a/db/migrate/20171002103314_add_poll_shift_task_index.rb b/db/migrate/20171002103314_add_poll_shift_task_index.rb
new file mode 100644
index 000000000..d15275556
--- /dev/null
+++ b/db/migrate/20171002103314_add_poll_shift_task_index.rb
@@ -0,0 +1,7 @@
+class AddPollShiftTaskIndex < ActiveRecord::Migration
+  def change
+    remove_index "poll_shifts", name: "index_poll_shifts_on_booth_id_and_officer_id"
+    add_index :poll_shifts, :task
+    add_index :poll_shifts, [:booth_id, :officer_id, :task], unique: true
+  end
+end
diff --git a/db/schema.rb b/db/schema.rb
index 500f03540..f6ff7447d 100644
--- a/db/schema.rb
+++ b/db/schema.rb
@@ -11,7 +11,7 @@
 #
 # It's strongly recommended that you check this file into your version control system.
 
-ActiveRecord::Schema.define(version: 20170927110953) do
+ActiveRecord::Schema.define(version: 20171002103314) do
 
   # These are extensions that must be enabled in order to support this database
   enable_extension "plpgsql"
@@ -701,9 +701,10 @@ ActiveRecord::Schema.define(version: 20170927110953) do
     t.integer  "task",          default: 0, null: false
   end
 
-  add_index "poll_shifts", ["booth_id", "officer_id"], name: "index_poll_shifts_on_booth_id_and_officer_id", using: :btree
+  add_index "poll_shifts", ["booth_id", "officer_id", "task"], name: "index_poll_shifts_on_booth_id_and_officer_id_and_task", unique: true, using: :btree
   add_index "poll_shifts", ["booth_id"], name: "index_poll_shifts_on_booth_id", using: :btree
   add_index "poll_shifts", ["officer_id"], name: "index_poll_shifts_on_officer_id", using: :btree
+  add_index "poll_shifts", ["task"], name: "index_poll_shifts_on_task", using: :btree
 
   create_table "poll_total_results", force: :cascade do |t|
     t.integer "author_id"