At a press conference, Sims played a voicemail message she received at the county office Wednesday night.
"I wish you had an email address up on your site," the tape begins, before lurching into a profanity laced tirade.
"I understand why you don't because you don't want to hear anything from your constituents. I'm very disappointed in your vote. You flip-flopped. Actually, you lied. And I hope you get **** AIDS and die. I pray to God you get AIDS and die. You **** liar. You're a **** liar."
The tape ends with racist remarks.
Earlier this week, Sims changed her mind on a county tax hike and effectively stopped a board movement to overturn Board president Todd Stroger’s veto.
The 13-4 vote meant that Cook County would retain the highest taxes of any county in the country.
It was hailed as a victory for Stroger.
At the conference, Sims said that she serves poor and affluent people, and that she made her decision to vote for the people "that needed it the most."
Sims also denied that she'd flip-flopped.
"There was no flip flop," she said, before adding "If people are still sending those kinds of messages, where is this country going?"
President Stroger condemned the messages, calling them "assaultive and nakedly threatening."
"Commissioner Sims has my wholehearted support and appreciation, not just for the courageous vote she took Tuesday, but in any all all efforts to secure her safety and well-being from those who threaten harm to her." Stroger said.