Public role and explicit rights

I gave a developer rights to the Public role on a SQL Server 2000 database. The Public role only has explicitly set select rights to the system tables and one user table. There are no other explicit rights set. The developer was able to open a table that had no rights set in enterprise manager and change data. Is this possible?

What are are the rights in Public if an object doesn't have them explicitly set?

Thanx for your responses in advance,

andy

resolved, someone put him in a group with greater permissions