If myself and my spouse do not complete a Health Assessment my employer will deduct $10 per week from my pay. Is that legal? How can they force their employees to answer personal, medical questions and if they refuse, penalize them monetarily?

Are you sure its an EXTRA deduction from your pay if you don't and not a discount if you do it? For me it's a discount if I do. ITs legal to give a discount to fill something out... and not offer the discount to those who won't. Not sure about the making you pay $10 extra if you don't.

No, it's mandatory and if you don't complete it $10 per week is deducted from your pay.

Is this for Michaels inc? I recently had to do the same thing, and I REALLY question the legality behind it.