<p>Unaccredited colleges and technical colleges won’t check the database - they will just accept the money from the student. Every single UC and Cal State is a member of the clearinghouse and will check (ethics-challenged posters considering lying on applications should check the member listing if they doubt me 
).</p>
<p>Also, many schools will not check at application time - they will admit the student and then do the check only on those who accept the offer of admission. If it is a large school, the student may have already started classes (and paid tuition) by the time the omission is discovered.</p>