FASB and Sarbanes Oxley have established auditing oversight which can be helpful in that we have auditors auditing the auditors. For every day regular companies, I think another great idea is to have internal audit support. AND internal audit oversight. So how do employees of a company watch over other employees of the same company? It's a challenge. Here is a link to an article from the JOA that discusses some of the steps a company can take in establishing an internal audit committee:

https://www.journalofaccountancy.com/issues/2013/aug/20137713.html (Links to an external site.)Links to an external site.