$this->input->post() not escaping JS

Why this $this->input->post() not escaping JS scripts?

Example what will happen if someone type in textarea <script>alert('test');</script>?
Will be added in the database as it is and the script will be executed where this textarea will be shown.

Any suggestions?

Here is the var_dump from $this->input->post();

PHP Code:

array (size=1)
  'message' => string '<script>alert('test');</script>' (length=31)