diff --git a/packages/backend/src/auth/guards/usager-note-access.guard.ts b/packages/backend/src/auth/guards/usager-note-access.guard.ts
index 766a523ba7..c1e956f011 100644
--- a/packages/backend/src/auth/guards/usager-note-access.guard.ts
+++ b/packages/backend/src/auth/guards/usager-note-access.guard.ts
@@ -50,7 +50,8 @@ export class UsagerNoteAccessGuard implements CanActivate {
       r.usagerNote = usagerNote;
       return r;
     } catch (e) {
-      appLogger.error("[UsagerNoteAccessGuard] usager doc not found", {
+      appLogger.error(e);
+      appLogger.error("[UsagerNoteAccessGuard] usager note not found", {
         sentry: true,
         context: {
           usagerRef,
diff --git a/packages/backend/src/modules/structures/controllers/structure-doc.controller.ts b/packages/backend/src/modules/structures/controllers/structure-doc.controller.ts
index a8495a03b4..a68b31085f 100644
--- a/packages/backend/src/modules/structures/controllers/structure-doc.controller.ts
+++ b/packages/backend/src/modules/structures/controllers/structure-doc.controller.ts
@@ -81,6 +81,7 @@ export class StructureDocController {
 
   @ApiOperation({ summary: "Upload de documents personnalisables" })
   @Post("")
+  @AllowUserStructureRoles("responsable", "admin")
   @UseInterceptors(
     FileInterceptor("file", {
       limits: FILES_SIZE_LIMIT,
@@ -193,6 +194,7 @@ export class StructureDocController {
   }
 
   @Delete(":uuid")
+  @AllowUserStructureRoles("responsable", "admin")
   public async deleteDocument(
     @Param("uuid", new ParseUUIDPipe()) uuid: string,
     @CurrentUser() user: UserStructureAuthenticated,
diff --git a/packages/backend/src/usagers/controllers/usagers-decision.controller.ts b/packages/backend/src/usagers/controllers/usagers-decision.controller.ts
index 479b36ec9a..95424b787f 100644
--- a/packages/backend/src/usagers/controllers/usagers-decision.controller.ts
+++ b/packages/backend/src/usagers/controllers/usagers-decision.controller.ts
@@ -2,6 +2,7 @@ import {
   Body,
   Controller,
   Delete,
+  ForbiddenException,
   Get,
   HttpStatus,
   Param,
@@ -34,11 +35,10 @@ import {
   UsagerDecision,
   UsagerNote,
   Usager,
-  UsagerDecisionStatut,
-  UserStructureRole,
 } from "@domifa/common";
 import { format } from "date-fns";
 import { getLastInteractionOut } from "../../modules/interactions/services";
+import { canAddDecision } from "../guards";
 
 @Controller("usagers-decision")
 @ApiTags("usagers-decision")
@@ -61,18 +61,9 @@ export class UsagersDecisionController {
     // eslint-disable-next-line @typescript-eslint/no-unused-vars
     @Param("usagerRef", new ParseIntPipe()) _usagerRef: number
   ): Promise<Usager> {
-    const decisionsToCheck: UsagerDecisionStatut[] = [
-      "ATTENTE_DECISION",
-      "INSTRUCTION",
-    ];
-    const rightsToCheck: UserStructureRole[] = ["responsable", "admin"];
-    if (
-      !decisionsToCheck.includes(decision.statut) &&
-      !rightsToCheck.includes(user.role)
-    ) {
-      throw new Error("CANNOT_SET_DECISION");
+    if (!canAddDecision(user.role, decision.statut)) {
+      throw new ForbiddenException("INSUFFICIENT_PERMISSIONS_FOR_DECISION");
     }
-
     decision.userName = `${user.prenom} ${user.nom}`;
     decision.userId = user.id;
 
diff --git a/packages/backend/src/usagers/decorators/index.ts b/packages/backend/src/usagers/decorators/index.ts
new file mode 100644
index 0000000000..3583c6b9df
--- /dev/null
+++ b/packages/backend/src/usagers/decorators/index.ts
@@ -0,0 +1,2 @@
+// @index('./*decorator.ts', f => `export * from '${f.path}'`)
+export * from "./validate-search-field.decorator";
diff --git a/packages/backend/src/usagers/utils/validate-search-field.decorator.ts b/packages/backend/src/usagers/decorators/validate-search-field.decorator.ts
similarity index 93%
rename from packages/backend/src/usagers/utils/validate-search-field.decorator.ts
rename to packages/backend/src/usagers/decorators/validate-search-field.decorator.ts
index 42809a8a77..f96474483c 100644
--- a/packages/backend/src/usagers/utils/validate-search-field.decorator.ts
+++ b/packages/backend/src/usagers/decorators/validate-search-field.decorator.ts
@@ -3,7 +3,7 @@ import {
   registerDecorator,
   ValidationArguments,
 } from "class-validator";
-import { validateSearchField } from "./validate-search-field";
+import { validateSearchField } from "../utils/validate-search-field";
 
 export function ValidateSearchField(validationOptions?: ValidationOptions) {
   return function (object: object, propertyName: string) {
diff --git a/packages/backend/src/usagers/dto/search-usager.dto.ts b/packages/backend/src/usagers/dto/search-usager.dto.ts
index c9924280cb..4908e8fe71 100644
--- a/packages/backend/src/usagers/dto/search-usager.dto.ts
+++ b/packages/backend/src/usagers/dto/search-usager.dto.ts
@@ -9,7 +9,7 @@ import {
   UsagersFilterCriteriaEntretien,
 } from "@domifa/common";
 import { Transform } from "class-transformer";
-import { ValidateSearchField } from "../utils";
+import { ValidateSearchField } from "../decorators";
 
 export class SearchUsagerDto {
   @ApiProperty({
diff --git a/packages/backend/src/usagers/guards/can-add-decision.spec.ts b/packages/backend/src/usagers/guards/can-add-decision.spec.ts
new file mode 100644
index 0000000000..0560b593e0
--- /dev/null
+++ b/packages/backend/src/usagers/guards/can-add-decision.spec.ts
@@ -0,0 +1,69 @@
+import { UserStructureRole, UsagerDecisionStatut } from "@domifa/common";
+import { canAddDecision } from "./can-add-decision";
+
+interface TestCase {
+  role: UserStructureRole;
+  decisionStatut: UsagerDecisionStatut;
+  expectedAccess: boolean;
+}
+
+describe("canAddDecision", () => {
+  const testCases: TestCase[] = [
+    { role: "facteur", decisionStatut: "INSTRUCTION", expectedAccess: false },
+    {
+      role: "facteur",
+      decisionStatut: "ATTENTE_DECISION",
+      expectedAccess: false,
+    },
+    { role: "facteur", decisionStatut: "RADIE", expectedAccess: false },
+    { role: "facteur", decisionStatut: "VALIDE", expectedAccess: false },
+    { role: "facteur", decisionStatut: "REFUS", expectedAccess: false },
+
+    { role: "agent", decisionStatut: "INSTRUCTION", expectedAccess: false },
+    {
+      role: "agent",
+      decisionStatut: "ATTENTE_DECISION",
+      expectedAccess: false,
+    },
+    { role: "agent", decisionStatut: "RADIE", expectedAccess: false },
+    { role: "agent", decisionStatut: "VALIDE", expectedAccess: false },
+    { role: "agent", decisionStatut: "REFUS", expectedAccess: false },
+
+    { role: "simple", decisionStatut: "INSTRUCTION", expectedAccess: true },
+    {
+      role: "simple",
+      decisionStatut: "ATTENTE_DECISION",
+      expectedAccess: true,
+    },
+    { role: "simple", decisionStatut: "RADIE", expectedAccess: true },
+    { role: "simple", decisionStatut: "VALIDE", expectedAccess: false },
+    { role: "simple", decisionStatut: "REFUS", expectedAccess: false },
+
+    {
+      role: "responsable",
+      decisionStatut: "INSTRUCTION",
+      expectedAccess: true,
+    },
+    {
+      role: "responsable",
+      decisionStatut: "ATTENTE_DECISION",
+      expectedAccess: true,
+    },
+    { role: "responsable", decisionStatut: "RADIE", expectedAccess: true },
+    { role: "responsable", decisionStatut: "VALIDE", expectedAccess: true },
+    { role: "responsable", decisionStatut: "REFUS", expectedAccess: true },
+
+    { role: "admin", decisionStatut: "INSTRUCTION", expectedAccess: true },
+    { role: "admin", decisionStatut: "ATTENTE_DECISION", expectedAccess: true },
+    { role: "admin", decisionStatut: "RADIE", expectedAccess: true },
+    { role: "admin", decisionStatut: "VALIDE", expectedAccess: true },
+    { role: "admin", decisionStatut: "REFUS", expectedAccess: true },
+  ];
+
+  test.each(testCases)(
+    'Rôle "$role" avec statut "$decisionStatut" doit retourner $expectedAccess',
+    ({ role, decisionStatut, expectedAccess }) => {
+      expect(canAddDecision(role, decisionStatut)).toBe(expectedAccess);
+    }
+  );
+});
diff --git a/packages/backend/src/usagers/guards/can-add-decision.ts b/packages/backend/src/usagers/guards/can-add-decision.ts
new file mode 100644
index 0000000000..03b53d7e41
--- /dev/null
+++ b/packages/backend/src/usagers/guards/can-add-decision.ts
@@ -0,0 +1,22 @@
+import { UserStructureRole, UsagerDecisionStatut } from "@domifa/common";
+
+export const canAddDecision = (
+  userRole: UserStructureRole,
+  decisionStatus: UsagerDecisionStatut
+): boolean => {
+  const instructRoles: UserStructureRole[] = ["simple", "responsable", "admin"];
+  const validateOrRefuseRoles: UserStructureRole[] = ["responsable", "admin"];
+
+  const canInstruct = instructRoles.includes(userRole);
+  const canValidateOrRefuse = validateOrRefuseRoles.includes(userRole);
+
+  const permissions: { [key in UsagerDecisionStatut]: boolean } = {
+    INSTRUCTION: canInstruct,
+    ATTENTE_DECISION: canInstruct,
+    RADIE: canInstruct,
+    VALIDE: canValidateOrRefuse,
+    REFUS: canValidateOrRefuse,
+  };
+
+  return permissions[decisionStatus];
+};
diff --git a/packages/backend/src/usagers/guards/index.ts b/packages/backend/src/usagers/guards/index.ts
new file mode 100644
index 0000000000..c7d96acbd6
--- /dev/null
+++ b/packages/backend/src/usagers/guards/index.ts
@@ -0,0 +1,2 @@
+// @index('./*guard.ts', f => `export * from '${f.path}'`)
+export * from "./can-add-decision";
diff --git a/packages/backend/src/usagers/utils/index.ts b/packages/backend/src/usagers/utils/index.ts
index e9c4b92045..83efa1b4b3 100644
--- a/packages/backend/src/usagers/utils/index.ts
+++ b/packages/backend/src/usagers/utils/index.ts
@@ -2,6 +2,5 @@
 export * from "./cerfa";
 export * from "./custom-docs";
 export * from "./dataCleanerForStats.service";
-export * from "./validate-search-field.decorator";
 export * from "./validate-search-field";
 export * from "./xlsx-structure-usagers-renderer";
diff --git a/packages/backend/src/usagers/utils/validate-search-field.ts b/packages/backend/src/usagers/utils/validate-search-field.ts
index c854d7ddea..53a575872f 100644
--- a/packages/backend/src/usagers/utils/validate-search-field.ts
+++ b/packages/backend/src/usagers/utils/validate-search-field.ts
@@ -11,25 +11,22 @@ export function validateSearchField(
   }
 
   try {
-    switch (searchField) {
-      case CriteriaSearchField.BIRTH_DATE:
-        const cleanDate = value.replace(/\D/g, "");
-        if (cleanDate.length !== 8) {
-          throw new BadRequestException(
-            'Format de date invalide. La date doit être au format "jj/mm/aaaa"'
-          );
-        }
+    if (searchField === CriteriaSearchField.BIRTH_DATE) {
+      const cleanDate = value.replace(/\D/g, "");
+      if (cleanDate.length !== 8) {
+        throw new BadRequestException(
+          'Format de date invalide. La date doit être au format "jj/mm/aaaa"'
+        );
+      }
 
-        const parsedDate = parse(cleanDate, "ddMMyyyy", new Date());
-        if (!isValid(parsedDate)) {
-          throw new BadRequestException(
-            "Date invalide. Vérifiez que le jour et le mois sont corrects"
-          );
-        }
-        return true;
-      default:
-        return true;
+      const parsedDate = parse(cleanDate, "ddMMyyyy", new Date());
+      if (!isValid(parsedDate)) {
+        throw new BadRequestException(
+          "Date invalide. Vérifiez que le jour et le mois sont corrects"
+        );
+      }
     }
+    return true;
   } catch (error) {
     if (error instanceof BadRequestException) {
       throw error;