Boolean Property Getter and Setter Locking

Is there any reason why you would create locks around the getter and setter of a boolean property like this?

  private _lockObject = new object();
  private bool _myFlag;
  public bool MyFlag
  {
    get
    {
      lock (_lockObject)
      {
        return _myFlag;
      }
    }
    set
    {
      lock (_lockObject)
      {
        _myFlag = value;
      }
    }
  }