When checkbox is marked from a user, another user to see a page and a form with radio buttons

I'm newbie and I don't know how to make when a user with definite role mark a checkbox, user with another role to see a page and a form with radio buttons. I'm using Codeigniter. This is the checkbox:

<input type="checkbox" name="final[]"  >

And when it's marked, another user must see a page "decision" and this:

echo "<input type='radio' name='decision' id='decision' >";