diff --git a/src/simulator/scheduler.cc b/src/simulator/scheduler.cc
index 1d4c26d7b..7f6115017 100644
--- a/src/simulator/scheduler.cc
+++ b/src/simulator/scheduler.cc
@@ -84,10 +84,5 @@ Scheduler::Remove (EventId id, EventKey *key)
   assert (!RealIsEmpty ());
   return RealRemove (id, key);
 }
-bool 
-Scheduler::IsValid (EventId id)
-{
-  return RealIsValid (id);
-}
 
 }; // namespace ns3
diff --git a/src/simulator/scheduler.h b/src/simulator/scheduler.h
index 5177a74f2..654f53e3e 100644
--- a/src/simulator/scheduler.h
+++ b/src/simulator/scheduler.h
@@ -71,7 +71,6 @@ class Scheduler {
   Scheduler::EventKey PeekNextKey (void) const ;
   void RemoveNext (void);
   EventImpl *Remove (EventId id, EventKey *key);
-  bool IsValid (EventId id);
 
 private:
   /**
@@ -113,12 +112,6 @@ private:
    * This methods cannot be invoked if the list is empty.
    */
   virtual EventImpl *RealRemove (EventId id, EventKey *key) = 0;
-  /**
-   * \param id event id to validate
-   * \returns true if the event id identifies an existing valid
-   *      event stored in the event list and false otherwise.
-   */
-  virtual bool RealIsValid (EventId id) = 0;
 };
 
 }; // namespace ns3
diff --git a/src/simulator/simulator.cc b/src/simulator/simulator.cc
index d6cfb2540..243f1bebf 100644
--- a/src/simulator/simulator.cc
+++ b/src/simulator/simulator.cc
@@ -241,7 +241,6 @@ SimulatorPrivate::Remove (EventId ev)
 void
 SimulatorPrivate::Cancel (EventId id)
 {
-  assert (m_events->IsValid (id));
   EventImpl *ev = id.GetEventImpl ();
   ev->Cancel ();
 }