Can an employer force you to work more than your 8 hour shift?

Employers may hire employees and set thier hours as a condition of their employment.  this is the general practice for employees at will.  If the employer wants to change the hours of his employees he may do so.  you as the employee may decide whether you want to continue to work.  if you agree to work for the hours then you consent to the employment agreement to work those hours or be fired.  if you do not want to work those hours then you have to choice of quitting.  Unless the employer is increasing hours to force someone to quit - a pretext for discrimination  - there is nothing you can do to oppose it.  if you are fired for not working those hours you may be entitled to unemployment benefits due to the employer changing the nature of the job beyond your responsibilities.

My research suggests that FL law generally follows federal law on labor law issues.  The Fair Labor Standards Act (FLSA) does not limit the number of hours per day or per week that employees aged 16 years and older can be required to work.  However, overtime may be required.

This federal law requires that some employees be paid overtime when they work more than 40 hours a week.  The FLSA divides employees into categories of salaried employees.  These are the “salaried exempt,” who are not protected by overtime laws, and the “non-exempt,” who are entitled to overtime.  Exempt employees are “executives” or administrators”and they are not entitled to overtime.  This depends on job duties for example the employee must have direction over at least two other people, and must be responsible for significant decision-making. 

Note:  Some exceptions apply under special circumstances to police and firefighters and to employees of hospitals and nursing homes.

According to the Department of Labor, unless exempted from the overtime regulations, employees covered by the Act must receive overtime pay for hours worked in excess of 40 in a workweek at a rate not less than time and one-half their regular rates of pay.