That's hard to say, but if anyone has access to that database, they can create and run a delete query, or just open the table, select the data and click the delete button.
As rainman89 stated, hopefully you had a backup (which given your stated question, I seriously doubt). But, if it was on a network drive and your network admin is backing the drives up, you might not be out of luck, if they can restore the database file to a different location, then you could import the table missing the data back in.