We have DB data issue where data is duplicated in two tables. When the first table is updated, a trigger updates the second table.

Ideally we would like to lock down the database so that the second table cannot be updated by the user/application. Can that be done, if so, now?

It is my understanding that some DBA's like to lock users/applications out of the tables and do that with stored procs. Is there some way to setup the security such that triggers and stored procs can modify the table but the user/application cannot?