the best way to treat a bad employee for me is to let them go, before they corrupt other staffs you have working for you and it can be very detrimental to the growth of your business and can cause you so much loss and damage beyond repair, so let them go.If I am the one that employed the bad employers,I will treat them how the treat me as their boss,if the treat me badly I will also treat them badly but if they give me my respect I will respect them