diff --git a/extension/persistence/eclipselink/src/main/java/org/apache/polaris/extension/persistence/impl/eclipselink/PolarisEclipseLinkMetaStoreSessionImpl.java b/extension/persistence/eclipselink/src/main/java/org/apache/polaris/extension/persistence/impl/eclipselink/PolarisEclipseLinkMetaStoreSessionImpl.java
index 4570d4018..ef631f171 100644
--- a/extension/persistence/eclipselink/src/main/java/org/apache/polaris/extension/persistence/impl/eclipselink/PolarisEclipseLinkMetaStoreSessionImpl.java
+++ b/extension/persistence/eclipselink/src/main/java/org/apache/polaris/extension/persistence/impl/eclipselink/PolarisEclipseLinkMetaStoreSessionImpl.java
@@ -22,6 +22,7 @@
 import static org.eclipse.persistence.config.PersistenceUnitProperties.JDBC_URL;
 
 import com.google.common.base.Predicates;
+import jakarta.persistence.EntityExistsException;
 import jakarta.persistence.EntityManager;
 import jakarta.persistence.EntityManagerFactory;
 import jakarta.persistence.EntityTransaction;
@@ -261,7 +262,7 @@ public <T> T runInTransaction(
       }
     } catch (PersistenceException e) {
       if (e.toString().toLowerCase(Locale.ROOT).contains("duplicate key")) {
-        throw new IllegalStateException("Duplicate key error when persisting entity", e);
+        throw new EntityExistsException("Duplicate key error when persisting entity", e);
       } else {
         throw e;
       }
diff --git a/polaris-service/src/main/java/org/apache/polaris/service/admin/PolarisServiceImpl.java b/polaris-service/src/main/java/org/apache/polaris/service/admin/PolarisServiceImpl.java
index 8c1c72f3f..4fa7a223c 100644
--- a/polaris-service/src/main/java/org/apache/polaris/service/admin/PolarisServiceImpl.java
+++ b/polaris-service/src/main/java/org/apache/polaris/service/admin/PolarisServiceImpl.java
@@ -360,11 +360,7 @@ public Response assignPrincipalRole(
         request.getPrincipalRole().getName(),
         principalName);
     PolarisAdminService adminService = newAdminService(securityContext);
-    try {
-      adminService.assignPrincipalRole(principalName, request.getPrincipalRole().getName());
-    } catch (IllegalStateException e) {
-      throw new AlreadyExistsException("Grant already exists or resolution failed");
-    }
+    adminService.assignPrincipalRole(principalName, request.getPrincipalRole().getName());
     return Response.status(Response.Status.CREATED).build();
   }
 
@@ -406,12 +402,8 @@ public Response assignCatalogRoleToPrincipalRole(
         catalogName,
         principalRoleName);
     PolarisAdminService adminService = newAdminService(securityContext);
-    try {
-      adminService.assignCatalogRoleToPrincipalRole(
-          principalRoleName, catalogName, request.getCatalogRole().getName());
-    } catch (IllegalStateException e) {
-      throw new AlreadyExistsException("Grant already exists or resolution failed");
-    }
+    adminService.assignCatalogRoleToPrincipalRole(
+        principalRoleName, catalogName, request.getCatalogRole().getName());
     return Response.status(Response.Status.CREATED).build();
   }