diff --git a/libfprint/fp-device.h b/libfprint/fp-device.h
index e82cb535..31538b0a 100644
--- a/libfprint/fp-device.h
+++ b/libfprint/fp-device.h
@@ -143,6 +143,7 @@ typedef enum {
  * @FP_DEVICE_ERROR_DATA_DUPLICATE: Enrolling template duplicates storaged templates
  * @FP_DEVICE_ERROR_REMOVED: The device has been removed.
  * @FP_DEVICE_ERROR_TOO_HOT: The device might be getting too hot
+ * @FP_DEVICE_ERROR_UNTRUSTED: Device cannot be trusted
  *
  * Error codes for device operations. More specific errors from other domains
  * such as #G_IO_ERROR or #G_USB_DEVICE_ERROR may also be reported.
@@ -161,6 +162,7 @@ typedef enum {
   /* Leave some room to add more DATA related errors */
   FP_DEVICE_ERROR_REMOVED = 0x100,
   FP_DEVICE_ERROR_TOO_HOT,
+  FP_DEVICE_ERROR_UNTRUSTED,
 } FpDeviceError;
 
 GQuark fp_device_retry_quark (void);
diff --git a/libfprint/fpi-device.c b/libfprint/fpi-device.c
index a1be30c0..191d9ab8 100644
--- a/libfprint/fpi-device.c
+++ b/libfprint/fpi-device.c
@@ -190,6 +190,9 @@ fpi_device_error_new (FpDeviceError error)
 
     case FP_DEVICE_ERROR_TOO_HOT:
       msg = "Device disabled to prevent overheating.";
+
+    case FP_DEVICE_ERROR_UNTRUSTED:
+      msg = "Could not verify integrity of the device, it cannot be trusted!";
       break;
 
     default: