diff --git a/app/helpers/application_helper.rb b/app/helpers/application_helper.rb
index dbc16a10f..7fddc56a0 100644
--- a/app/helpers/application_helper.rb
+++ b/app/helpers/application_helper.rb
@@ -30,4 +30,11 @@ module ApplicationHelper
       root_path
     end
   end
+
+  def ensure_safe_json(json)
+    JSON.parse(json).to_json
+  rescue Exception => e
+    Raven.capture_exception(e)
+    {}
+  end
 end
diff --git a/app/views/new_gestionnaire/dossiers/_map.html.haml b/app/views/new_gestionnaire/dossiers/_map.html.haml
index 6ad0d9300..85ecbafc4 100644
--- a/app/views/new_gestionnaire/dossiers/_map.html.haml
+++ b/app/views/new_gestionnaire/dossiers/_map.html.haml
@@ -15,6 +15,6 @@
 
 :javascript
   var getPositionUrl = "#{position_gestionnaire_dossier_path(dossier.procedure, dossier)}";
-  var dossierJsonLatLngs = #{dossier.json_latlngs};
-  var dossierCadastres = #{dossier.cadastres.to_json};
-  var dossierQuartiersPrioritaires = #{dossier.quartier_prioritaires.to_json};
+  var dossierJsonLatLngs = #{raw(ensure_safe_json(dossier.json_latlngs))};
+  var dossierCadastres = #{raw(ensure_safe_json(dossier.cadastres.to_json))};
+  var dossierQuartiersPrioritaires = #{raw(ensure_safe_json(dossier.quartier_prioritaires.to_json))};
diff --git a/spec/helpers/application_helper_spec.rb b/spec/helpers/application_helper_spec.rb
index 30a7becef..22c2f9b06 100644
--- a/spec/helpers/application_helper_spec.rb
+++ b/spec/helpers/application_helper_spec.rb
@@ -17,4 +17,18 @@ describe ApplicationHelper do
       it { is_expected.to be_nil }
     end
   end
+
+  describe "#ensure_safe_json" do
+    subject { ensure_safe_json(json) }
+
+    context "with a dirty json" do
+      let(:json) { "alert('haha');" }
+      it { is_expected.to eq({}) }
+    end
+
+    context 'with a correct json' do
+      let(:json) { '[[{"lat": 2.0, "lng": 102.0}, {"lat": 3.0, "lng": 103.0}, {"lat": 2.0, "lng": 102.0}], [{"lat": 2.0, "lng": 102.0}, {"lat": 3.0, "lng": 103.0}, {"lat": 2.0, "lng": 102.0}]]' }
+      it { is_expected.to eq("[[{\"lat\":2.0,\"lng\":102.0},{\"lat\":3.0,\"lng\":103.0},{\"lat\":2.0,\"lng\":102.0}],[{\"lat\":2.0,\"lng\":102.0},{\"lat\":3.0,\"lng\":103.0},{\"lat\":2.0,\"lng\":102.0}]]") }
+    end
+  end
 end
diff --git a/spec/views/new_gestionnaire/dossiers/_map_spec.rb b/spec/views/new_gestionnaire/dossiers/_map_spec.rb
new file mode 100644
index 000000000..b74392134
--- /dev/null
+++ b/spec/views/new_gestionnaire/dossiers/_map_spec.rb
@@ -0,0 +1,27 @@
+require 'spec_helper'
+
+describe 'new_gestionnaire/dossiers/_map.html.haml', type: :view do
+  subject do
+    render(partial: 'new_gestionnaire/dossiers/map.html.haml', locals: { dossier: dossier })
+  end
+
+  describe "javascript variables printing" do
+    let(:dossier) { create(:dossier, :with_entreprise, json_latlngs: json_latlngs) }
+
+    context 'with a correct json' do
+      let(:json_latlngs) { "[[{\"lat\":50.659255436656736,\"lng\":3.080635070800781},{\"lat\":50.659255436656736,\"lng\":3.079690933227539},{\"lat\":50.659962770886516,\"lng\":3.0800342559814453},{\"lat\":50.659962770886516,\"lng\":3.0811500549316406},{\"lat\":50.659255436656736,\"lng\":3.080635070800781}]]" }
+
+      before { subject }
+
+      it { expect(rendered).to have_content('var dossierJsonLatLngs = [[{"lat":50.659255436656736,"lng":3.080635070800781},{"lat":50.659255436656736,"lng":3.079690933227539},{"lat":50.659962770886516,"lng":3.0800342559814453},{"lat":50.659962770886516,"lng":3.0811500549316406},{"lat":50.659255436656736,"lng":3.080635070800781}]];') }
+    end
+
+    context 'without a correct json' do
+      let(:json_latlngs) { "dossier" }
+
+      before { subject }
+
+      it { expect(rendered).to have_content('var dossierJsonLatLngs = {};') }
+    end
+  end
+end