What is the reason behind the new overtime laws?
First a correction: the changes are not new laws. The changes are updates to rules of which the Department of Labor is the legal custodian. The answer: Because the guidelines have not been updated in too long. The revised guidelines increase all of the limits to include more low-income jobs. The old regulations allowed workers being paid over $250 per week to be exempt from the overtime regulations, the new rule is $455 per week. Most of the changes are like this. Certain rules for computer-related jobs have been added because they did not exist when the rules were first established. It appears to me to be a reasonable revision to update outdated aspects of existing rules. Some of the changes will allow jobs that were not exempt before to be exempt. Many jobs that had been exempt will not be any more. Most of the hourly jobs where I work were over the old limit and still complied with overtime regulations. I suspect this is the most common case. See http://www.dol.gov/esa/regs/complian
