diff --git a/include/ircd/m/room/auth.h b/include/ircd/m/room/auth.h
index c2bc12ee2..3bcc3f781 100644
--- a/include/ircd/m/room/auth.h
+++ b/include/ircd/m/room/auth.h
@@ -21,6 +21,7 @@ struct ircd::m::room::auth
 	using types = vector_view<const string_view>;
 	using events_view = vector_view<const event *>;
 	using passfail = std::tuple<bool, std::exception_ptr>;
+	IRCD_M_EXCEPTION(m::error, error, http::INTERNAL_SERVER_ERROR)
 	IRCD_M_EXCEPTION(error, FAIL, http::UNAUTHORIZED)
 
 	static bool is_power_event(const event &);
diff --git a/modules/m_room_auth.cc b/modules/m_room_auth.cc
index befd64222..8c30ce8ae 100644
--- a/modules/m_room_auth.cc
+++ b/modules/m_room_auth.cc
@@ -161,6 +161,7 @@ ircd::m::room::auth::passfail
 IRCD_MODULE_EXPORT
 ircd::m::room::auth::check(std::nothrow_t,
                            const event &event)
+try
 {
 	using json::at;
 
@@ -244,6 +245,13 @@ ircd::m::room::auth::check(std::nothrow_t,
 
 	return ret;
 }
+catch(const std::exception &)
+{
+	return
+	{
+		false, std::current_exception()
+	};
+}
 
 ircd::m::room::auth::passfail
 IRCD_MODULE_EXPORT