Should I have to thread-protect an event sink method?

Hi

I am using this code to send client a message (it is called whenever a log line is added at server):

 ev := (getServer.EventRepository.GetWriter<IHTTPLogEvents>(EmptyGUID));
 ev.Event.OnSendLog(FormatLog(aLogItem));

Should I have to protect it using CriticalSection? Like:

FCS.Enter;
  try
     ev := (EventRepository.GetWriter<IHTTPLogEvents>(Session.SessionID));
     ev.Event.OnSendLog('test' );
  finally
    FCS.Leave;
  end;

Hi,

critical session isn’t required