diff --git a/app/models/assign_to.rb b/app/models/assign_to.rb
index 7a41960e1..07ddde607 100644
--- a/app/models/assign_to.rb
+++ b/app/models/assign_to.rb
@@ -14,8 +14,8 @@
 #  procedure_id                                :integer
 #
 class AssignTo < ApplicationRecord
-  belongs_to :instructeur
-  belongs_to :groupe_instructeur
+  belongs_to :instructeur, optional: false
+  belongs_to :groupe_instructeur, optional: false
   has_one :procedure_presentation, dependent: :destroy
   has_one :procedure, through: :groupe_instructeur
 
diff --git a/spec/controllers/users/dossiers_controller_spec.rb b/spec/controllers/users/dossiers_controller_spec.rb
index 29d8fbeb7..311018640 100644
--- a/spec/controllers/users/dossiers_controller_spec.rb
+++ b/spec/controllers/users/dossiers_controller_spec.rb
@@ -400,8 +400,8 @@ describe Users::DossiersController, type: :controller do
 
         before do
           allow(DossierMailer).to receive(:notify_new_dossier_depose_to_instructeur).and_return(double(deliver_later: nil))
-          create(:assign_to, instructeur: instructeur_with_instant_email_dossier, procedure: dossier.procedure, instant_email_dossier_notifications_enabled: true, groupe_instructeur: dossier.procedure.defaut_groupe_instructeur)
-          create(:assign_to, instructeur: instructeur_without_instant_email_dossier, procedure: dossier.procedure, instant_email_dossier_notifications_enabled: false, groupe_instructeur: dossier.procedure.defaut_groupe_instructeur)
+          create(:assign_to, instructeur: instructeur_with_instant_email_dossier, procedure: dossier.procedure, instant_email_dossier_notifications_enabled: true)
+          create(:assign_to, instructeur: instructeur_without_instant_email_dossier, procedure: dossier.procedure, instant_email_dossier_notifications_enabled: false)
         end
 
         it "sends notification mail to instructeurs" do
@@ -838,8 +838,8 @@ describe Users::DossiersController, type: :controller do
       allow(DossierMailer).to receive(:notify_new_commentaire_to_instructeur).and_return(double(deliver_later: nil))
       instructeur_with_instant_message.follow(dossier)
       instructeur_without_instant_message.follow(dossier)
-      create(:assign_to, instructeur: instructeur_with_instant_message, procedure: procedure, instant_email_message_notifications_enabled: true, groupe_instructeur: procedure.defaut_groupe_instructeur)
-      create(:assign_to, instructeur: instructeur_without_instant_message, procedure: procedure, instant_email_message_notifications_enabled: false, groupe_instructeur: procedure.defaut_groupe_instructeur)
+      create(:assign_to, instructeur: instructeur_with_instant_message, procedure: procedure, instant_email_message_notifications_enabled: true)
+      create(:assign_to, instructeur: instructeur_without_instant_message, procedure: procedure, instant_email_message_notifications_enabled: false)
     end
 
     after { Timecop.return }
diff --git a/spec/factories/assign_to.rb b/spec/factories/assign_to.rb
index 64955c283..facc4a0ff 100644
--- a/spec/factories/assign_to.rb
+++ b/spec/factories/assign_to.rb
@@ -1,11 +1,5 @@
 FactoryBot.define do
   factory :assign_to do
-    after(:build) do |assign_to, evaluator|
-      if evaluator.groupe_instructeur.persisted?
-        assign_to.groupe_instructeur = evaluator.groupe_instructeur
-      else
-        assign_to.groupe_instructeur = assign_to.procedure.defaut_groupe_instructeur
-      end
-    end
+    groupe_instructeur { procedure.defaut_groupe_instructeur }
   end
 end
diff --git a/spec/factories/procedure_presentation.rb b/spec/factories/procedure_presentation.rb
index 17f6a0c27..28d0d1433 100644
--- a/spec/factories/procedure_presentation.rb
+++ b/spec/factories/procedure_presentation.rb
@@ -1,6 +1,10 @@
 FactoryBot.define do
   factory :procedure_presentation do
-    assign_to { create(:assign_to, procedure: create(:procedure, :with_type_de_champ)) }
+    transient do
+      procedure { create(:procedure, :with_instructeur, :with_type_de_champ) }
+    end
+
+    assign_to { association :assign_to, procedure: procedure, instructeur: procedure.instructeurs.first }
     sort { { "table" => "user", "column" => "email", "order" => "asc" } }
   end
 end
diff --git a/spec/models/assign_to_spec.rb b/spec/models/assign_to_spec.rb
index adec8da2b..bce7b7a1a 100644
--- a/spec/models/assign_to_spec.rb
+++ b/spec/models/assign_to_spec.rb
@@ -1,7 +1,7 @@
 describe AssignTo, type: :model do
   describe '#procedure_presentation_or_default_and_errors' do
     let(:procedure) { create(:procedure) }
-    let(:assign_to) { create(:assign_to, procedure: procedure) }
+    let(:assign_to) { create(:assign_to, procedure: procedure, instructeur: create(:instructeur)) }
 
     let(:procedure_presentation_and_errors) { assign_to.procedure_presentation_or_default_and_errors }
     let(:procedure_presentation_or_default) { procedure_presentation_and_errors.first }
diff --git a/spec/models/instructeur_spec.rb b/spec/models/instructeur_spec.rb
index 2e69ce40c..e6db4ed56 100644
--- a/spec/models/instructeur_spec.rb
+++ b/spec/models/instructeur_spec.rb
@@ -389,7 +389,7 @@ describe Instructeur, type: :model do
     let(:procedure_to_assign) { create(:procedure) }
 
     before do
-      create(:assign_to, instructeur: instructeur, procedure: procedure_to_assign, daily_email_notifications_enabled: true, groupe_instructeur: procedure_to_assign.defaut_groupe_instructeur)
+      create(:assign_to, instructeur: instructeur, procedure: procedure_to_assign, daily_email_notifications_enabled: true)
     end
 
     context 'when a dossier in construction exists' do
diff --git a/spec/models/procedure_presentation_spec.rb b/spec/models/procedure_presentation_spec.rb
index 2b66781b8..a35bcd257 100644
--- a/spec/models/procedure_presentation_spec.rb
+++ b/spec/models/procedure_presentation_spec.rb
@@ -1,10 +1,11 @@
 describe ProcedurePresentation do
   let(:procedure) { create(:procedure, :with_type_de_champ, :with_type_de_champ_private) }
-  let(:assign_to) { create(:assign_to, procedure: procedure) }
+  let(:instructeur) { create(:instructeur) }
+  let(:assign_to) { create(:assign_to, procedure: procedure, instructeur: instructeur) }
   let(:first_type_de_champ) { assign_to.procedure.types_de_champ.first }
   let(:first_type_de_champ_id) { first_type_de_champ.id.to_s }
   let(:procedure_presentation) {
-    ProcedurePresentation.create(
+    create(:procedure_presentation,
       assign_to: assign_to,
       displayed_fields: [
         { "label" => "test1", "table" => "user", "column" => "email" },
@@ -86,7 +87,7 @@ describe ProcedurePresentation do
         procedure.types_de_champ_private[3].update_attribute(:type_champ, TypeDeChamp.type_champs.fetch(:explication))
       end
 
-      subject { create(:procedure_presentation, assign_to: create(:assign_to, procedure: procedure)) }
+      subject { create(:procedure_presentation, assign_to: assign_to) }
 
       it { expect(subject.fields).to eq(expected) }
     end
@@ -96,7 +97,7 @@ describe ProcedurePresentation do
       let(:surname_field) { { "label" => "Nom", "table" => "individual", "column" => "nom" } }
       let(:gender_field) { { "label" => "Civilité", "table" => "individual", "column" => "gender" } }
       let(:procedure) { create(:procedure, :for_individual) }
-      let(:procedure_presentation) { create(:procedure_presentation, assign_to: create(:assign_to, procedure: procedure)) }
+      let(:procedure_presentation) { create(:procedure_presentation, assign_to: assign_to) }
 
       subject { procedure_presentation.fields }
 
@@ -105,7 +106,7 @@ describe ProcedurePresentation do
   end
 
   describe "#fields_for_select" do
-    subject { create(:procedure_presentation) }
+    subject { create(:procedure_presentation, assign_to: assign_to) }
 
     before do
       allow(subject).to receive(:fields).and_return([
@@ -126,7 +127,7 @@ describe ProcedurePresentation do
   end
 
   describe '#get_value' do
-    let(:procedure_presentation) { ProcedurePresentation.create(assign_to: assign_to, displayed_fields: [{ 'table' => table, 'column' => column }]) }
+    let(:procedure_presentation) { create(:procedure_presentation, procedure: procedure, assign_to: assign_to, displayed_fields: [{ 'table' => table, 'column' => column }]) }
 
     subject { procedure_presentation.displayed_field_values(dossier).first }
 
@@ -168,6 +169,7 @@ describe ProcedurePresentation do
 
     context 'for individual table' do
       let(:table) { 'individual' }
+      let(:procedure) { create(:procedure, :for_individual, :with_type_de_champ, :with_type_de_champ_private) }
       let(:dossier) { create(:dossier, procedure: procedure, individual: create(:individual, nom: 'Martin', prenom: 'Jacques', gender: 'M.')) }
 
       context 'for prenom column' do
@@ -248,7 +250,7 @@ describe ProcedurePresentation do
     let(:instructeur) { create(:instructeur) }
     let(:assign_to) { create(:assign_to, procedure: procedure, instructeur: instructeur) }
     let(:sort) { { 'table' => table, 'column' => column, 'order' => order } }
-    let(:procedure_presentation) { ProcedurePresentation.create(assign_to: assign_to, sort: sort) }
+    let(:procedure_presentation) { create(:procedure_presentation, assign_to: assign_to, sort: sort) }
 
     subject { procedure_presentation.sorted_ids(procedure.dossiers, instructeur) }
 
@@ -416,7 +418,7 @@ describe ProcedurePresentation do
   end
 
   describe '#filtered_ids' do
-    let(:procedure_presentation) { create(:procedure_presentation, assign_to: create(:assign_to, procedure: procedure), filters: { "suivis" => filter }) }
+    let(:procedure_presentation) { create(:procedure_presentation, assign_to: assign_to, filters: { "suivis" => filter }) }
 
     subject { procedure_presentation.filtered_ids(procedure.dossiers.joins(:user), 'suivis') }
 
@@ -755,7 +757,7 @@ describe ProcedurePresentation do
   end
 
   describe '#eager_load_displayed_fields' do
-    let(:procedure_presentation) { ProcedurePresentation.create(assign_to: assign_to, displayed_fields: [{ 'table' => table, 'column' => column }]) }
+    let(:procedure_presentation) { create(:procedure_presentation, procedure: procedure, assign_to: assign_to, displayed_fields: [{ 'table' => table, 'column' => column }]) }
     let!(:dossier) { create(:dossier, :en_construction, procedure: procedure) }
     let(:displayed_dossier) { procedure_presentation.eager_load_displayed_fields(procedure.dossiers).first }