http://www.cnn.com/2017/02/20/us/workers-fired-day-without-immigrants/Jim Serowski's employees told him they'd planned to skip work Thursday to participate in "A Day Without Immigrants," the nationwide day of protest.
Serowski, founder of JVS Masonry in Commerce City, Colorado, said his position to them was clear: "If you're going to stand up for what you believe in, you have to be willing to pay the price." As promised, when Serowski's foreman and some 30 bricklayers failed to show up for work, he fired them all with no regrets, he said.
Bill McNally, owner of I Don't Care Bar and Grill in Catoosa, Oklahoma, said his 12 line cooks gave him no heads-up that they planned to participate in the day of action. They didn't even call to say they were not coming in.
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Not sure how it works in other states, but in Los Angeles County, employees have six 'paid' sick days that they can also use if you are sick, or emergencies. Not just for taking off work. Also, many in Los Angeles County use this as six 'personal' days in which you can request off when needed even if you are not sick, etc.
But if these employers had a policy of letting employees go if they don't show up for work and not calling in sick (which you need a note), then they have every right to fire someone, IF they have shown that they did that in the past and were not discriminatory.