diff --git a/app/controllers/backoffice/dossiers_controller.rb b/app/controllers/backoffice/dossiers_controller.rb
index 3273384ee..205904f59 100644
--- a/app/controllers/backoffice/dossiers_controller.rb
+++ b/app/controllers/backoffice/dossiers_controller.rb
@@ -107,12 +107,12 @@ class Backoffice::DossiersController < Backoffice::DossiersListController
   def process_dossier
     create_dossier_facade params[:dossier_id]
 
-    if params[:dossier] && params[:dossier][:motivation].present?
-      motivation = params[:dossier][:motivation]
-    end
-
     dossier = @facade.dossier
 
+    if params[:dossier] && params[:dossier][:motivation].present?
+      dossier.motivation = params[:dossier][:motivation]
+    end
+
     case params[:process_action]
     when "refuse"
       dossier.refuse!
@@ -129,10 +129,6 @@ class Backoffice::DossiersController < Backoffice::DossiersListController
       template = dossier.procedure.closed_mail_template
     end
 
-    if motivation
-      dossier.motivation = motivation
-    end
-
     dossier.save
 
     # needed to force Carrierwave to provide dossier.attestation.pdf.read
diff --git a/app/controllers/new_gestionnaire/dossiers_controller.rb b/app/controllers/new_gestionnaire/dossiers_controller.rb
index 1041bc2e4..af2cead4c 100644
--- a/app/controllers/new_gestionnaire/dossiers_controller.rb
+++ b/app/controllers/new_gestionnaire/dossiers_controller.rb
@@ -76,7 +76,7 @@ module NewGestionnaire
 
     def terminer
       if params[:dossier] && params[:dossier][:motivation].present?
-        motivation = params[:dossier][:motivation]
+        dossier.motivation = params[:dossier][:motivation]
       end
 
       case params[:process_action]
@@ -95,10 +95,6 @@ module NewGestionnaire
         template = procedure.closed_mail_template
       end
 
-      if motivation
-        dossier.motivation = motivation
-      end
-
       dossier.save
 
       # needed to force Carrierwave to provide dossier.attestation.pdf.read
diff --git a/spec/controllers/backoffice/dossiers_controller_spec.rb b/spec/controllers/backoffice/dossiers_controller_spec.rb
index ed9250a87..b51574792 100644
--- a/spec/controllers/backoffice/dossiers_controller_spec.rb
+++ b/spec/controllers/backoffice/dossiers_controller_spec.rb
@@ -349,6 +349,22 @@ describe Backoffice::DossiersController, type: :controller do
           end
         end
       end
+
+      context 'when the attestation template uses the motivation field', focus: true do
+        let(:emailable) { false }
+        let(:template) { create(:attestation_template) }
+        let(:procedure) { create(:procedure, :published, attestation_template: template, gestionnaires: [gestionnaire]) }
+
+        subject { post :process_dossier, params: { process_action: "close", dossier_id: dossier_id, dossier: { motivation: "Yallah" }}}
+
+        before do
+          expect_any_instance_of(AttestationTemplate)
+            .to receive(:attestation_for)
+            .with(have_attributes(motivation: "Yallah"))
+        end
+
+        it { subject }
+      end
     end
   end
 
diff --git a/spec/controllers/new_gestionnaire/dossiers_controller_spec.rb b/spec/controllers/new_gestionnaire/dossiers_controller_spec.rb
index 71738ce3a..fc016440c 100644
--- a/spec/controllers/new_gestionnaire/dossiers_controller_spec.rb
+++ b/spec/controllers/new_gestionnaire/dossiers_controller_spec.rb
@@ -223,6 +223,27 @@ describe NewGestionnaire::DossiersController, type: :controller do
           end
         end
       end
+
+      context 'when the attestation template uses the motivation field', focus: true do
+        let(:emailable) { false }
+        let(:template) { create(:attestation_template) }
+        let(:procedure) { create(:procedure, :published, attestation_template: template, gestionnaires: [gestionnaire]) }
+
+        subject do
+          post :terminer, params: { process_action: "accepter",
+                                    procedure_id: procedure.id,
+                                    dossier_id: dossier.id,
+                                    dossier: { motivation: "Yallah" }}
+        end
+
+        before do
+          expect_any_instance_of(AttestationTemplate)
+            .to receive(:attestation_for)
+            .with(have_attributes(motivation: "Yallah"))
+        end
+
+        it { subject }
+      end
     end
   end