It is not necessarily illegal for your employer to make changes to your timesheet, which records your work hours. Perhaps you use an electronic system at work where you log into a computer and clock in for the day, and you log back out at the end of your shift. Your employer likely has administrative access, so they can also log you in and out or change the times that were previously recorded.
The key for employers to remember is that this always has to be done accurately and fairly. The goal should be to maintain accurate records to ensure that all employees are paid correctly.
For instance, say that your shift starts at seven in the morning. One day, you are feeling rather tired, and you simply forget to log in. You do not remember until 10 in the morning, when you take a break and realize that your hours have not been tracked. If you log in at 10, but your employer later alters the time to 7:00 a.m., it is just accurately representing the hours you actually worked.
When it becomes wage theft
Problems arise if your employer makes alterations that reduce your pay when those changes are not accurate.
For instance, perhaps you work 42 hours during a week, and so you are owed overtime pay. Your employer changes the time that you worked on Friday to bring it back down to 40 hours, hoping not to pay time and a half. This is a form of wage theft because you are losing out on compensation that you deserve.
So, while your employer may have legal access to those records, changes can still be problematic. Make sure you know what legal steps to take during a wage and hour dispute.