Taxing authority is the legal power to require people and businesses to pay money into a public treasury, and in the United States it is held by three levels of elected government: Congress, state legislatures, and local bodies like county commissions and city councils. Each level draws that power from a specific constitutional source, exercises it through statutes its elected members vote on, and operates under enforceable limits that keep it from becoming arbitrary. No agency, court, or executive can create a tax on its own.
Where Federal Taxing Power Comes From
The federal government’s power to tax begins with Article I, Section 8, Clause 1 of the Constitution, known as the Taxing and Spending Clause. It gives Congress authority to “lay and collect Taxes, Duties, Imposts and Excises, to pay the Debts and provide for the common Defence and general Welfare of the United States.”1Legal Information Institute. U.S. Constitution Annotated – Overview of Spending Clause That single sentence is the origin point for virtually every federal tax that exists today.
The original Constitution also constrained that power. Article I, Section 9, Clause 4 requires that any “direct” tax be divided among the states based on population.2Congress.gov. ArtI.S9.C4.1 Overview of Direct Taxes In practice, Congress would set the total to be raised and assign each state a share proportional to its census count. That made a federal income tax nearly impossible to administer, since wealthier and poorer states with equal population would owe the same share.
The 16th Amendment, ratified in 1913, removed the obstacle. It gave Congress the power to tax income “from whatever source derived, without apportionment among the several States, and without regard to any census or enumeration.”3National Archives. 16th Amendment to the U.S. Constitution: Federal Income Tax (1913) Individual and corporate income taxes, which now fund the majority of federal spending, trace directly to that amendment.
Who Writes Federal Tax Law and Who Administers It
The Constitution puts tax legislation firmly in the legislative branch. Article I, Section 7 requires that all revenue bills start in the House of Representatives, though the Senate may propose amendments.4Congress.gov. ArtI.S7.C1.1 Origination Clause and Revenue Bills The body closest to voters has to move first before money can be extracted from the public.
Once a tax law passes, administration shifts to the executive branch. The Secretary of the Treasury holds general authority over enforcement of the Internal Revenue Code.5Office of the Law Revision Counsel. 26 USC 7801 – Authority of Department of the Treasury Day-to-day operations run through the Commissioner of Internal Revenue, whose statutory duties include directing execution of federal tax laws and related treaties.6Office of the Law Revision Counsel. 26 USC 7803 – Commissioner of Internal Revenue
The IRS is not the only federal agency exercising taxing authority. The Alcohol and Tobacco Tax and Trade Bureau collects federal excise taxes on alcohol, tobacco, firearms, and ammunition, and regulates alcohol production, importation, and wholesale distribution.7The United States Government Manual. Alcohol and Tobacco Tax and Trade Bureau U.S. Customs and Border Protection collects tariffs on imported goods. Each agency operates within its own statutory lane.
State and Local Taxing Authority
States draw taxing power from a different source. The 10th Amendment reserves to the states all powers not granted to the federal government, and the authority to fund state operations through taxation has always been treated as one of those reserved powers.8Legal Information Institute. U.S. Constitution Annotated – Federal Power to Tax and the Tenth Amendment State legislatures pass the income, sales, and excise taxes their residents pay, and they choose which mix to use. Five states impose no sales tax at all; others rely heavily on it. Most states levy an individual income tax, and 44 impose a corporate income tax.
States routinely delegate taxing authority downward to counties, cities, school districts, and special-purpose districts like water or transit authorities. County commissions and city councils set property tax rates and local sales tax add-ons under authority granted by state constitutions or statutes. A single paycheck or purchase can be subject to taxes from several overlapping jurisdictions.
Reaching Across State Lines
A state can only tax activity with a sufficient connection to its borders. Until 2018, that generally required physical presence before a state could force a business to collect sales tax. The Supreme Court changed that rule in South Dakota v. Wayfair, holding that a substantial economic presence is enough. Most states now require remote sellers to collect sales tax once they exceed $100,000 in in-state sales, though some set the threshold higher. The Court emphasized that states still cannot discriminate against or place excessive burdens on interstate commerce.9Legal Information Institute. U.S. Constitution Annotated – State Taxation and the Dormant Commerce Clause
Constitutional Limits on the Power to Tax
The same Constitution that grants taxing authority also constrains it. The Uniformity Clause requires that federal indirect taxes, meaning excise taxes, duties, and similar levies, operate the same way in every part of the country. A federal excise on gasoline must apply at the same rate in every state.10Legal Information Institute. The Uniformity Clause and Indirect Taxes The Direct Tax Clause still requires apportionment by population for any tax classified as direct, other than income taxes exempted by the 16th Amendment.2Congress.gov. ArtI.S9.C4.1 Overview of Direct Taxes This requirement is why Congress relies overwhelmingly on income and excise taxes.
State taxing power faces its own limits. The Commerce Clause prevents states from taxing interstate business in ways that discriminate against out-of-state companies or impose burdens clearly excessive relative to local benefits.11Legal Information Institute. State Taxation and the Dormant Commerce Clause The 14th Amendment’s Due Process and Equal Protection Clauses add further guardrails, requiring that state tax laws bear a rational relationship to a legitimate government purpose and not single out particular groups arbitrarily.
How Long the Power Lasts
Taxing authority is also limited by time. The IRS generally has three years from the date you file a return to assess additional tax for that year.12Office of the Law Revision Counsel. 26 USC 6501 – Limitations on Assessment and Collection Once a tax is assessed, the IRS has ten years to collect it through a levy or court proceeding.13Office of the Law Revision Counsel. 26 USC 6502 – Collection After Assessment After that ten-year window closes, the debt expires.
Several exceptions widen these windows. The three-year clock never starts if you never file. There is no time limit on assessment when a return is fraudulent. If you leave out more than 25% of your gross income, the assessment period extends to six years, and failing to report required foreign financial accounts or assets worth more than $5,000 also triggers a six-year window.14Internal Revenue Service. Overview of Statute of Limitations on the Assessment of Tax
What Taxing Authority Lets the Government Do
Taxing authority carries real teeth. The IRS can examine any return, and when an audit turns up underpaid tax the taxpayer will not agree to, the IRS issues a statutory notice of deficiency, sometimes called a 90-day letter.15Internal Revenue Service. IRM 4.8.9 Statutory Notices of Deficiency
If a tax debt goes unpaid after formal demand, a federal tax lien automatically attaches to all your property and rights to property, including real estate, bank accounts, and future income.16Office of the Law Revision Counsel. 26 USC 6321 – Lien for Taxes A lien protects the government’s claim; a levy actually takes property. Ten days after the IRS sends notice and demand, it has authority to seize and sell property, garnish wages, or take funds from bank accounts.17Office of the Law Revision Counsel. 26 USC 6331 – Levy and Distraint Before levying, the IRS must issue a Notice of Intent to Levy that gives you 30 days to request a Collection Due Process hearing.18Internal Revenue Service. Collection Due Process (CDP) FAQs
Civil penalties escalate quickly. Failing to file on time costs 5% of the unpaid tax per month, up to 25%; failing to pay adds another 0.5% per month, also capped at 25%; and interest compounds daily on top of both.19Office of the Law Revision Counsel. 26 USC 6651 – Failure to File Tax Return or to Pay Tax20Internal Revenue Service. Topic No. 653, IRS Notices and Bills, Penalties and Interest Charges The most severe tool is criminal prosecution. Willful tax evasion is a felony carrying up to five years in prison and fines of up to $100,000 for individuals and $500,000 for corporations.21Office of the Law Revision Counsel. 26 USC 7201 – Attempt to Evade or Defeat Tax Filing a fraudulent return is a separate felony punishable by up to three years in prison.22Office of the Law Revision Counsel. 26 USC 7206 – Fraud and False Statements
What Pushes Back on That Power
Taxpayers hold enforceable rights against overreach. The IRS recognizes ten rights under the Taxpayer Bill of Rights, including the right to be informed, the right to pay no more than the correct amount, the right to challenge IRS decisions and be heard, and the right to appeal in an independent forum.23Internal Revenue Service. Taxpayer Bill of Rights
If you receive a notice of deficiency, you have 90 days to petition the U.S. Tax Court to contest the amount before paying anything, or 150 days if you are outside the country.24Office of the Law Revision Counsel. 26 USC 6213 – Restrictions Applicable to Deficiencies; Petition to Tax Court While a Tax Court case is pending, the IRS generally cannot assess or collect the disputed tax. Miss the deadline, and the remaining option is to pay in full and sue for a refund in federal district court or the U.S. Court of Federal Claims.
The Taxpayer Advocate Service operates as an independent organization within the IRS. If you cannot resolve a problem through normal channels, or an IRS process is causing financial hardship, TAS can intervene. The National Taxpayer Advocate also reports to Congress annually on the most serious systemic problems taxpayers face.25Taxpayer Advocate Service. About Us It is a free resource that many taxpayers never learn about until a situation becomes serious.