Yes, it is. You would just need to have the visible property of the check box set to true if the test is passed.
If it is a value that you wish to store in your database, then of course the checkbox would have to be linked to a field in a table somewhere for later reference. Your example above is not worded completely correctly for the after update function, though.... but perhaps you know that already.
Additionally, assuming you are using a form which looks at a record in your database, I would suggest the Form detail on current event should also carry out the test for the checkbox visibility, then the checkbox will show correctly if you move to a different record.