How To Prepare Your Evidence for Tax Court

Your Tax Court case is moving toward trial. Maybe settlement talks broke down. Maybe you decided the IRS's offer wasn't good enough. Either way, you're preparing for the moment when a judge will look at the evidence and decide. (Many of the same evidence-gathering principles apply if you're preparing for an Appeals conference before filing a petition.)

The burden of proof is on you. That means bringing the right documents, understanding what the judge needs to see, and knowing what to do when your records aren't perfect. Pro se petitioners who go to trial prevail in full or in part about 12% of the time, compared to about 23% for represented petitioners. Evidence preparation is one of the biggest factors that separates those who prevail from those who don't.

The Burden of Proof Is on You

The default rule in Tax Court is straightforward: the IRS's determination in your Notice of Deficiency is presumed correct, and you must prove it wrong. You can't just say "I disagree." You need documents, records, or credible testimony showing that the IRS got it wrong.

The standard is called preponderance of the evidence—you must show it is more likely than not that the IRS's determination is incorrect. This is a lower bar than the "beyond a reasonable doubt" standard used in criminal cases, but it still requires real proof.

The Tax Court's own guidance puts it plainly: "The burden of proof is generally on the petitioner. This means that you need to bring to court evidence, such as documents and testimony of witnesses (you and maybe others), to prove that the determination of the IRS is not correct." (Tax Court: During Trial)

When the Burden Shifts to the IRS

Under IRC § 7491(a), the burden of proof can shift to the IRS on a factual issue—but only if you meet all four conditions:

1. You introduce credible evidence on that issue
2. You comply with substantiation requirements under the tax code
3. You maintain required records under IRC § 6001
4. You cooperate with reasonable IRS requests for documents and information

In practice, this shift matters in a narrow subset of cases. If you failed to keep adequate records—the very reason many deductions get disallowed—the burden doesn't shift. The practical takeaway: prepare your evidence as if the burden is on you, because it almost always is.

Penalties Are Different

For penalties, the IRS bears the initial burden of production under IRC § 7491(c). The IRS must first come forward with evidence that the penalty applies. Once it does, the burden shifts to you to show reasonable cause or another defense under IRC § 6664(c). For more on penalty defenses, see How To Request IRS Penalty Abatement.

The IRS must also show written supervisory approval of the penalty under IRC § 6751(b). If it can't, the penalty fails regardless of the merits.

What Evidence the Tax Court Accepts

Under IRC § 7453, the Tax Court generally follows the rules of evidence used in federal district courts. Tax Court Rule 143 spells out how this works in practice.

Documents are your strongest evidence. Receipts, bank statements, contracts, invoices, cancelled checks, tax returns, and IRS transcripts all carry significant weight. The best documents are contemporaneous—created at or near the time of the transaction, not reconstructed later.

Copies are acceptable. Under Rule 143(e), a copy is admissible to the same extent as an original unless a genuine question is raised about the original's authenticity. You don't need to produce the originals.

Testimony is evidence, but it has limits. You can and should testify on your own behalf. Third-party witnesses with direct knowledge of the facts can also testify. But testimony alone—without supporting documents—is usually not enough to carry the burden of proof.

Some items are not evidence. Letters you sent to the IRS during the audit, claims in your petition, and statements in your briefs are not evidence (Rule 143(c)). Documents you previously gave to the IRS examiner are not part of the record in your Tax Court case unless you formally introduce them through stipulation or as an exhibit at trial.

Substantiation Requirements for Common Disputes

Different types of disputes have different evidence requirements. Here are the ones that affect most pro se petitioners. Many of these documentation standards also apply during the audit itself—gathering records early can resolve issues before they reach Tax Court. See How To Respond to an IRS Audit for what to prepare at the examination stage.

Deductions: General Business Expenses

For general business expenses under IRC § 162, you must prove the expense was paid, the amount, and the business purpose. Receipts, invoices, bank statements, and credit card records showing the vendor and amount are the foundation.

Deductions: Travel, Meals, and Vehicle Use

IRC § 274(d) imposes strict substantiation requirements for travel expenses, business gifts, and listed property (including vehicles). For these expenses, you need contemporaneous records showing:

• The amount of the expense
• The date and place (or date and description for gifts)
• The business purpose
• The business relationship to the person receiving the benefit

Under Treasury Regulation § 1.274-5, "contemporaneous" means records maintained at or near the time of the expenditure—a log, diary, or expense report. Receipts are required for lodging and any single expense over $75. A cancelled check alone is not enough without evidence of business purpose.

This is where many pro se petitioners lose. Without a contemporaneous log, the Court cannot estimate the amount. The deduction is entirely disallowed—not reduced.

Charitable Contributions

IRC § 170 has tiered documentation requirements that escalate with the amount:

• Under $250: A cancelled check, bank record, or written receipt from the organization
• $250 or more: A contemporaneous written acknowledgment from the recipient organization, obtained by the earlier of the filing date or the return due date. Without it, the deduction is entirely disallowed
• Over $5,000 (noncash property): A qualified appraisal must be obtained, and a summary—Form 8283, Section B—must be attached to the return. The full appraisal stays in your records
• Over $500,000 (noncash property): The full qualified appraisal itself must be attached to the return, not just the summary form

Unreported Income

When the IRS determines you had unreported income, it often uses the bank deposits method—reconstructing income by analyzing deposits in your bank accounts. Per IRM 4.10.4, the IRS identifies deposits and treats unexplained ones as income.

To rebut a bank deposits case, you need to identify each deposit the IRS is treating as income and show it came from a nontaxable source. Gather:

• Bank statements from all accounts for the years at issue
• Loan agreements and promissory notes for borrowed funds
• Documentation of gifts received
• Records of transfers between your own accounts
• Third-party statements from anyone who deposited funds into your account

Penalties

For accuracy-related penalties under IRC § 6662, the IRS must first show the penalty applies. Your defense is reasonable cause—that you acted in good faith and with ordinary business care (IRC § 6664(c)). Evidence that supports reasonable cause includes:

• Written advice from a tax professional (CPA, enrolled agent, or attorney)
• Proof that you provided complete and accurate information to that advisor
• Documentation showing the complexity of the tax issue
• Records showing you made a good-faith effort to comply

When Records Are Missing: The Cohan Rule

What happens when you know you incurred an expense but can't prove the exact amount? The Cohan rule—named after Cohan v. Commissioner, 39 F.2d 540 (2d Cir. 1930)—provides that where a taxpayer establishes they incurred a deductible expense but cannot substantiate the exact amount, the Court may estimate a reasonable allowance. The estimate will be conservative, and the Court bears heavily against the taxpayer whose imprecise records are their own doing.

To invoke the Cohan rule, you must establish:

1. The expense was actually incurred (not just claimed)
2. The expense was of a deductible nature
3. There is some reasonable basis for the Court to make an estimate

Even partial records help. A few months of receipts, bank statements showing a pattern, or testimony about regular business practices can give the judge enough to work with.

Where Cohan Does Not Apply

The Cohan rule does not apply to expenses subject to strict substantiation under IRC § 274(d)—travel, business gifts, and listed property. For these, if you lack contemporaneous records, the deduction is entirely disallowed. The Court cannot estimate.

Cohan also does not apply where the tax code imposes a specific documentation requirement, such as the contemporaneous written acknowledgment for charitable contributions of $250 or more.

Secondary Evidence

If original records are lost, look for alternatives: credit card statements, calendar entries, appointment books, emails, photographs, or correspondence that corroborate the expense. If records were destroyed by a disaster (fire, flood, theft), document the loss—this strengthens both your Cohan argument and any reasonable cause defense for penalties.

Organizing Your Evidence

The Tax Court doesn't want a box of unsorted papers. Organize your evidence by disputed issue—match each exhibit to the specific adjustment the IRS made.

For each issue, lay out three things: what the IRS says, what you say, and the document that proves your position. Label exhibits clearly using the Tax Court's numbering convention—number first, then party designation (1-P, 2-P, 3-P for petitioner exhibits; 1-R, 2-R for respondent; 1-J, 2-J for joint) and prepare an exhibit list. You'll need this for your pretrial memorandum, which must list every witness you plan to call (with a summary of expected testimony), all remaining disputed issues, and your legal authorities.

Bring three copies of every exhibit that the IRS has not stipulated—one for the judge, one for the IRS attorney, and one for yourself.

Key Deadlines Before Trial

The Standing Pretrial Order sets a countdown of deadlines working backward from your trial session:

Evidence not properly exchanged or filed by these deadlines may be excluded. Under Tax Court Rule 149, failure to produce evidence on an issue where you bear the burden can result in dismissal or a determination against you on that issue.

Stipulations

Stipulations are binding. Under Tax Court Rule 91, stipulated facts are treated as conclusive admissions. Don't stipulate to anything you're uncertain about—but don't refuse to stipulate to genuinely undisputed facts either, or you risk sanctions (penalties imposed by the judge, which can include monetary fines under IRC § 6673). For the full stipulation negotiation process and how to respond to IRS discovery requests, see How To Handle Discovery and Pretrial Preparation.

Your Testimony

In most pro se cases, you are the primary witness. Your testimony is evidence, but the Tax Court evaluates it carefully. Self-serving, uncorroborated testimony is generally given little weight.

The judge assesses credibility based on your demeanor, consistency, and whether your testimony is corroborated by documents. Specific testimony—"my records show I paid $3,200 on March 15"—is far stronger than vague testimony—"I think I spent about $3,000 sometime that spring."

Prepare for the IRS attorney's cross-examination. The attorney will focus on gaps in your documentation and inconsistencies between your testimony and the records. Know what the IRS's evidence says about your case so you can address discrepancies.

If you have witnesses—an accountant, business partner, or someone with direct knowledge of the facts—bring them if their testimony adds something your documents don't already show.

What Happens at Trial

On the first day of the trial session, the judge holds a calendar call—each case on the calendar is called, and you must be present and respond. The judge then schedules specific trial times. For a walkthrough of the full post-filing timeline, see What Happens After You File Your Tax Court Petition.

At trial, the typical sequence is:

1. Opening statements (optional, not under oath)—a brief summary of your case and what your evidence will show
2. Your case—you present your evidence first (documents and testimony), since you bear the burden of proof
3. Cross-examination—the IRS attorney questions you and your witnesses
4. IRS's case—the IRS presents its evidence and witnesses, if any
5. The judge may ask questions throughout—Tax Court judges are active participants

After both sides close their cases, the judge may issue a decision from the bench, request post-trial briefs, or take the case under advisement. A written opinion follows. For a detailed walkthrough of the entire trial day—from calendar call to the judge's decision—see What To Expect at Your Tax Court Trial.

Common Evidence Mistakes

Relying on testimony alone. Judges want documents. "I paid it" without a receipt or bank statement is usually not enough.

Bringing everything unsorted. Dumping a box of papers on the judge's bench hurts your credibility. Organize by issue.

Not exchanging documents before trial. The Standing Pretrial Order requires document exchange 14 days before trial. Evidence submitted late may be excluded.

Stipulating too much—or too little. Don't agree to facts you dispute. But refusing to stipulate undisputed facts leads to sanctions and a motion to compel.

Ignoring the IRS's evidence. Read the IRS's proposed stipulations and exhibits carefully. Know what they're relying on so you can respond.

Not getting your transcripts. Your account transcript shows what the IRS assessed and when. It can reveal errors in the IRS's position.

Strengthening Your Position Before Trial

Start gathering evidence as soon as you file your petition—don't wait for a trial date. While your case is pending, the IRS cannot collect the disputed tax, giving you time to prepare. Request your IRS transcripts early. If records are missing, begin reconstruction now: contact banks for duplicate statements, request receipts from vendors, and reach out to charities for acknowledgment letters.

Strong evidence also strengthens your settlement position. An Appeals officer or IRS attorney who sees organized documentation with clear support for your claims is more likely to offer favorable terms. Most (76%) of Tax Court cases settle before trial—and the strength of your evidence shapes those settlements.

If you need help, a Low Income Taxpayer Clinic can assist with evidence gathering and trial preparation if your income is below 250% of the poverty line and your dispute is $50,000 or less. Even late in the process, representation improves outcomes.

Resources

• Tax Court Guidance: Before Trial—the Court's official pre-trial guide
• Tax Court Guidance: During Trial—what to expect on trial day
• Tax Court Rule 91—Stipulations for Trial
• Tax Court Rule 143—Evidence
• Tax Court Rule 149—Failure To Appear or To Adduce Evidence
• Standing Pretrial Order—Regular Cases (sample)
• Standing Pretrial Order—Small Tax Cases (sample)
• IRC § 7491—Burden of Proof
• IRC § 274—Strict Substantiation Requirements
• IRC § 170—Charitable Contributions
• IRC § 6662—Accuracy-Related Penalty
• Treas. Reg. § 1.274-5—Substantiation Requirements
• DAWSON Portal—monitor your case and file documents
• IRS LITC Directory—find free legal help
• What Happens After You File Your Tax Court Petition—procedural timeline including stipulations and pretrial memorandum
• How To Settle Your Tax Court Case—evaluating settlement offers and when to say no
• How To Get and Read Your IRS Transcripts—gathering key evidence
• How To Find and Use a Low Income Taxpayer Clinic—free representation for qualifying taxpayers
• How To File Your Tax Court Petition—the petition that started this process
• How IRC 6213 Protects You While Your Tax Court Case Is Pending—collection is paused while you prepare
• Small Case or Regular Case: Which Should You Choose?—procedural differences at trial

This article is for informational purposes only and does not constitute legal or tax advice. For advice specific to your situation, consult a qualified tax professional or attorney.