As a compromise, Mayor Mick Cornett guaranteed if MAPS 3 passes, new police and fire jobs would be added with the help of a separate use tax.
That promise won over the previously skeptical district attorney.
"The city council and mayor's office have said clearly we care about public safety," said David Prater.
"If MAPS doesn't pass public safety, problems are going to multiply," said Mayor Mick Cornett.
Oklahoma City voters will get the final say on the issue, December 8th.