Aside from criminal background checks conducted by companies to screen their applicants, they also sometimes conduct a reference check to ensure that the prospective employee is not providing any false information from his previous employment.
More things about reference checking:
Reference checks and background checks are not the same things
If you are doing both background check and reference checks, make sure that you get useful insight from each and not just duplicating your work.
Reference checks, on the other hand, confirms the job titles and date of employment, learns the strengths and weaknesses, and better understand the previous job duties and experiences of the candidate.
Half of all resumes and job applications contain untruths