check without your approval, except legal garnishments, and they certainly can not deduct taxes - at least in the United States. As independant contractors, you are not really covered, in most cases, by labor laws. You also need to check the agreement you have with your employer, to see if some kind off fees are being legally withheld.
You should contact the labor department in the state you work in, or the federal labor department and ask them if you have some kind of case. Additionally, you might want to contact the IRS, because it may be that this company is not declaring all their income.
It would be great to get more information about the income you have as well as the deductions, so we have a clearer picture of what sounds like a scam.
It does sound like you have some kind of case, though, especially if this is happening to more than 100 people. You may be able to sue to get that money back.