Russia, Saudi Arabia, Ukraine, Serbia and the Republic of Abkhazia. Each of these countries use a flat tax system.
Dr. Ben Carson's Biblical tithe plan is essentially a 10% flat tax. Just like in Albania, Kazakhstan, Turkmenistan, Mongolia, and the Republic of Abkhazia.
More countries that have a flat tax system (Wiki page)
Michael Cohen’s Emails Were Sought by Special Counsel in July 2017, Documents Show - The records, released on Tuesday, indicate that Mr. Cohen, President Trump’s former lawyer, came under scrutiny soon after Mr. Trump took office.
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