diff --git a/pkgs/shelf_router/lib/src/router.dart b/pkgs/shelf_router/lib/src/router.dart
index 51f96fd..ca4dbb8 100644
--- a/pkgs/shelf_router/lib/src/router.dart
+++ b/pkgs/shelf_router/lib/src/router.dart
@@ -19,9 +19,6 @@
 
 /// Get a URL parameter captured by the [Router].
 String params(Request request, String name) {
-  ArgumentError.checkNotNull(request, 'request');
-  ArgumentError.checkNotNull(name, 'name');
-
   final p = request.context['shelf_router/params'];
   if (!(p is Map<String, String>)) {
     throw Exception('no such parameter $name');
@@ -101,7 +98,6 @@
   /// `HEAD` is always wrong. To explicitely implement a `HEAD` handler it must
   /// be registered before the `GET` handler.
   void add(String verb, String route, Function handler) {
-    ArgumentError.checkNotNull(verb, 'verb');
     if (!isHttpMethod(verb)) {
       throw ArgumentError.value(verb, 'verb', 'expected a valid HTTP method');
     }
@@ -124,8 +120,6 @@
   ///
   /// In this case prefix may not contain any parameters, nor
   void mount(String prefix, Handler handler) {
-    ArgumentError.checkNotNull(prefix, 'prefix');
-    ArgumentError.checkNotNull(handler, 'handler');
     if (!prefix.startsWith('/') || !prefix.endsWith('/')) {
       throw ArgumentError.value(
           prefix, 'prefix', 'must start and end with a slash');
diff --git a/pkgs/shelf_router/lib/src/router_entry.dart b/pkgs/shelf_router/lib/src/router_entry.dart
index 98fb3c0..4860ef3 100644
--- a/pkgs/shelf_router/lib/src/router_entry.dart
+++ b/pkgs/shelf_router/lib/src/router_entry.dart
@@ -17,8 +17,6 @@
 
 /// Check if the [regexp] is non-capturing.
 bool _isNoCapture(String regexp) {
-  ArgumentError.checkNotNull(regexp, 'regexp');
-
   // Construct a new regular expression matching anything containing regexp,
   // then match with empty-string and count number of groups.
   return RegExp('^(?:$regexp)|.*\$').firstMatch('')!.groupCount == 0;
@@ -57,9 +55,6 @@
   }) {
     middleware = middleware ?? ((Handler fn) => fn);
 
-    ArgumentError.checkNotNull(verb, 'verb');
-    ArgumentError.checkNotNull(route, 'route');
-    ArgumentError.checkNotNull(handler, 'handler');
     if (!route.startsWith('/')) {
       throw ArgumentError.value(
           route, 'route', 'expected route to start with a slash');