Its not timesheet/clock fraud to clock in when you get to work. timesheet fraud is putting down extra hours that you didn't actually do. For example, Larry works at an advertising agency. Joe's Repair Co. Hires Larry to do some work for them. Larry puts in 8 hours of actual work, but knows his boss requires a minimum of 12 hours every week and this was the only job Larry had all week. So he says he actually worked 12 hours and Joe's Repair Co. gets billed for 12 hours, 4 of which weren't actually worked. Its more common in consultancy type work where its hard to prove exactly how long was worked on things, and timesheets are usually only done once a week/month/project length, rather than every day.
Now if you have an actual timecard you clock in every day and then manually change either the timeclock or just the card itself, that would also be fraud. Or if you had a coworker take your timecard and clock in for you when you aren't actually there, that is fraud.
Clocking in WHEN YOU ARRIVE AT WORK is in no way fraud. The company may say they do not do any overtime whatsoever and won't pay for you if you go over or won't pay any time clocked in before the "start time", and they may disapprove of starting work early (to the point of firing people if they do it, most likely because of the above not wanting any overtime) but it is in no way fraud.
Now, as to clocking in early to take a shit, while its technically legal (you are clocking in when you are supposed to and you are required to be able to use the bathroom, even if it is as you arrive to work) Many states are At-will employment, and if the boss found out about it, would fire them on the spot or at least tell them to stop doing it. Even if they aren't At-will, no employee is 100% perfect, its not hard to find an excuse to fire somebody
Now if you have an actual timecard you clock in every day and then manually change either the timeclock or just the card itself, that would also be fraud. Or if you had a coworker take your timecard and clock in for you when you aren't actually there, that is fraud.
Now, as to clocking in early to take a shit, while its technically legal (you are clocking in when you are supposed to and you are required to be able to use the bathroom, even if it is as you arrive to work) Many states are At-will employment, and if the boss found out about it, would fire them on the spot or at least tell them to stop doing it. Even if they aren't At-will, no employee is 100% perfect, its not hard to find an excuse to fire somebody