diff --git a/lib/tasks/deployment/20220705164551_remove_unused_champs.rake b/lib/tasks/deployment/20220705164551_remove_unused_champs.rake
new file mode 100644
index 000000000..043708479
--- /dev/null
+++ b/lib/tasks/deployment/20220705164551_remove_unused_champs.rake
@@ -0,0 +1,34 @@
+namespace :after_party do
+  desc 'Deployment task: remove_unused_champs'
+  task remove_unused_champs: :environment do
+    puts "Running deploy task 'remove_unused_champs'"
+
+    child_champs = Champ.where.not(parent_id: nil).select(:id, :dossier_id, :type_de_champ_id)
+    progress = ProgressReport.new(child_champs.size)
+
+    types_de_champ_by_dossier = Hash.new do |hash, dossier_id|
+      dossier = Dossier.select(:revision_id).find_by(id: dossier_id)
+      if dossier.present?
+        hash[dossier_id] = ProcedureRevisionTypeDeChamp.where(revision_id: dossier.revision_id).pluck(:type_de_champ_id)
+      else
+        hash[dossier_id] = []
+      end
+    end
+
+    champs_to_destroy = []
+    child_champs.find_each do |champ|
+      if !types_de_champ_by_dossier[champ.dossier_id].include?(champ.type_de_champ_id)
+        champs_to_destroy.push(champ.id)
+      end
+      progress.inc
+    end
+    progress.finish
+
+    Champ.where(id: champs_to_destroy).destroy_all
+
+    # Update task as completed.  If you remove the line below, the task will
+    # run with every deploy (or every time you call after_party:run).
+    AfterParty::TaskRecord
+      .create version: AfterParty::TaskRecorder.new(__FILE__).timestamp
+  end
+end
diff --git a/spec/lib/tasks/deployment/20220705164551_remove_unused_champs_spec.rb b/spec/lib/tasks/deployment/20220705164551_remove_unused_champs_spec.rb
new file mode 100644
index 000000000..e38e0589c
--- /dev/null
+++ b/spec/lib/tasks/deployment/20220705164551_remove_unused_champs_spec.rb
@@ -0,0 +1,22 @@
+describe '20220705164551_remove_unused_champs' do
+  let(:rake_task) { Rake::Task['after_party:remove_unused_champs'] }
+  let(:procedure) { create(:procedure, :with_all_champs) }
+  let(:dossier) { create(:dossier, :with_populated_champs, procedure: procedure) }
+  let(:champ_repetition) { dossier.champs.find(&:repetition?) }
+
+  subject(:run_task) do
+    dossier
+    rake_task.invoke
+  end
+
+  before { champ_repetition.champs.first.update(type_de_champ: create(:type_de_champ)) }
+  after { rake_task.reenable }
+
+  describe 'remove_unused_champs' do
+    it "with bad champs" do
+      expect(Champ.where(dossier: dossier).count).to eq(39)
+      run_task
+      expect(Champ.where(dossier: dossier).count).to eq(38)
+    end
+  end
+end
diff --git a/spec/models/dossier_spec.rb b/spec/models/dossier_spec.rb
index 9f528c3c7..77542bba4 100644
--- a/spec/models/dossier_spec.rb
+++ b/spec/models/dossier_spec.rb
@@ -1556,8 +1556,9 @@ describe Dossier do
   end
 
   describe "#destroy" do
+    let(:procedure) { create(:procedure, :with_all_champs, :with_all_annotations) }
     let(:transfer) { create(:dossier_transfer) }
-    let(:dossier) { create(:dossier, transfer: transfer) }
+    let(:dossier) { create(:dossier, :with_populated_champs, :with_populated_annotations, transfer: transfer, procedure: procedure) }
 
     before do
       create(:dossier, transfer: transfer)
@@ -1566,6 +1567,12 @@ describe Dossier do
 
     it "can destroy dossier" do
       expect(dossier.destroy).to be_truthy
+      expect { dossier.reload }.to raise_error(ActiveRecord::RecordNotFound)
+    end
+
+    it "can reset demarche" do
+      expect { dossier.procedure.reset! }.not_to raise_error
+      expect { dossier.reload }.to raise_error(ActiveRecord::RecordNotFound)
     end
   end