Oracle Database Discussions

A debate is raging at my workplace between the app developers who write the stored procs used on their back end db and the data warehouse etl developers who are to use said stored procs. The app developers say that stored procs should never internally issue 'commit' statements and that only the calling connection should commit afterwards and that this is a general standard in the database world. The data warehouse etl group insist that it's perfectly OK for a stored proc to issue its own commit.
What are the standards where you work; do sp's commit internally or not? Is one way or the other the exception or the rule in typical Oracle practices?