diff --git a/app/models/avis.rb b/app/models/avis.rb
index cd8e7c532..8046edd2d 100644
--- a/app/models/avis.rb
+++ b/app/models/avis.rb
@@ -43,7 +43,7 @@ class Avis < ApplicationRecord
 
   validates :email, format: { with: Devise.email_regexp, message: "n'est pas valide" }, allow_nil: true
   validates :claimant, presence: true
-  validates :question_answer, presence: { on: :update, if: -> { question_label.present? } }
+  validates :question_answer, inclusion: { in: [true, false] }, on: :update, if: -> { question_label.present? }
   validates :piece_justificative_file, size: { less_than: FILE_MAX_SIZE }
   validates :introduction_file, size: { less_than: FILE_MAX_SIZE }
   before_validation -> { sanitize_email(:email) }
diff --git a/spec/system/experts/expert_spec.rb b/spec/system/experts/expert_spec.rb
index b78d1de56..9fe482596 100644
--- a/spec/system/experts/expert_spec.rb
+++ b/spec/system/experts/expert_spec.rb
@@ -100,15 +100,15 @@ describe 'Inviting an expert:' do
 
       # check validation
       click_on 'Envoyer votre avis'
-      expect(page).to have_content('Le champ « Réponse oui/non » doit être rempli')
+      expect(page).to have_content("Le champ « Réponse oui/non » n'est pas inclus(e) dans la liste")
 
-      choose 'oui'
+      choose 'non'
       fill_in 'avis_answer', with: 'Ma réponse d’expert.'
       click_on 'Envoyer votre avis'
 
       expect(page).to have_content('Votre réponse est enregistrée')
       expect(page).to have_content('Ma réponse d’expert.')
-      expect(page).to have_content('oui')
+      expect(page).to have_content('non')
 
       within('.breadcrumbs') { click_on 'Avis' }
       expect(page).to have_text('1 avis donné')