The finder
Start with the excuse category and the penalty section; those two filters reproduce how a court frames the question. The text search covers the caption, the citation, the one-line holding and the penalty descriptions, so extension, K-1, executor or 3520 narrow quickly. The summary strip counts outcomes for the current filter.
Classifications (excuse category, penalty section, outcome) are editorial summaries made for this finder; the opinion controls. Outcome counts describe litigated decisions, not administrative requests.
How to read a result
- Outcome. granted means the reasonable cause defense succeeded on every penalty litigated on that ground. partial means it succeeded for some penalties, years or items and failed for others, or the penalty fell for a different reason (for example IRC 6751(b) supervisory approval) while reasonable cause was rejected; the holding says which. denied means it failed on every penalty litigated. not decided is a ruling that did not reach the merits: a motion to dismiss or summary judgment denied because facts were disputed, or a remand. Those rulings are hidden until you tick the box, because a denial of the government’s motion is not a taxpayer win.
- Excuse tags. A decision can carry more than one tag when the taxpayer argued several things. Other collects incarceration, preoccupation with litigation or an audit, work demands, divorce, frivolous positions and cases where no evidence was offered.
- Holding. One or two sentences in the editor’s words, written from the opinion. Where the Commissioner bore the burden because the penalty was raised as new matter in the answer, the holding says so, because it changes how the case should be read (compare Higbee, 116 T.C. 438, on who must prove what).
- Key quote. Present on 145 records: a short passage copied from the opinion text and checked word for word against the saved copy. Line-number artifacts from numbered-line court PDFs were removed.
- Link. Tax Court decisions link to a copy of the opinion PDF hosted on this site (federal court opinions are public domain; the file is the one downloaded from DAWSON, unchanged), with a second link to the DAWSON docket record for the case; other courts link to the opinion PDF on govinfo.gov, the court’s site, or the Library of Congress (Boyle).
- Precedent. Tax Court summary opinions (IRC 7463(b)) and unpublished circuit opinions cannot be cited as precedent; they are here because they show how the standard is applied to ordinary facts. Memorandum opinions are citable but do not bind the court the way a reviewed or regular opinion does.
The numbers behind the filters
Across the 303 decisions, reasonable cause won outright in 28 (10 percent of the 286 decided on the merits) and in part in 34 (12 percent). The win rate differs sharply by penalty: the accuracy-related penalty, where IRC 6664(c) asks about reasonable cause and good faith for the return position, is where most wins sit; the failure-to-file addition, governed by Boyle, almost never yields; and IRC 6654 has no reasonable cause exception at all outside 6654(e)(3). The guide’s statistics section has the full tables by excuse and by penalty.
| Penalty | Granted | Partial | Denied | Not decided | Total |
|---|---|---|---|---|---|
| Accuracy-related, IRC 6662 and 6662A | 22 | 30 | 124 | 3 | 179 |
| Failure to file, IRC 6651(a)(1) | 6 | 19 | 136 | 5 | 166 |
| Failure to pay, IRC 6651(a)(2) | 4 | 6 | 81 | 4 | 95 |
| Fraudulent failure to file, IRC 6651(f) | 0 | 0 | 4 | 0 | 4 |
| Estimated tax, IRC 6654 | 0 | 2 | 46 | 0 | 48 |
| Failure to deposit, IRC 6656 | 1 | 1 | 16 | 2 | 20 |
| Fraud, IRC 6663 | 0 | 2 | 4 | 0 | 6 |
| Charitable appraisal requirement, IRC 170(f)(11) | 3 | 2 | 8 | 3 | 16 |
| Partnership and S corporation late filing, IRC 6698 and 6699 | 1 | 0 | 7 | 0 | 8 |
| Information returns, IRC 6721, 6722 and 6724 | 0 | 0 | 3 | 1 | 4 |
| International information returns, IRC 6038(b), 6039F, 6048 and 6677 | 0 | 0 | 3 | 4 | 7 |
Read the counts as litigated decisions only. Taxpayers whose requests were granted by a campus or by Appeals never reach a courtroom, so the rate here understates how often reasonable cause works administratively; it is a guide to which arguments survive scrutiny, not a forecast for a Form 843.
What is not in the dataset
- Tax Court opinions before 1995 are not in DAWSON, so cases cited inside later opinions (Estate of La Meres, Niedringhaus, Jackson, Beard) appear only through those citations, not as records.
- Appellate coverage is thin (12 decisions) and skewed to the Fifth Circuit. Decisions such as Oosterwijk (4th Cir.), Baccei (9th Cir.), East Wind (3d Cir.), Valen Manufacturing (6th Cir.) and Diamond Plating (7th Cir.) are discussed in opinions that are here but have no record of their own yet.
- Administrative outcomes: nothing here reflects First Time Abate, campus reasonable cause determinations or Appeals settlements. For those, start with reasonable cause under IRM 20.1.1.3.2 and the First Time Abate checker.
- Classification was done from the opinion text with a focus on the reasonable cause passages. For long opinions with several taxpayers or years, partial can hide detail; read the opinion before citing it.
Questions practitioners ask
Why are some district court rulings hidden by default?
Because a ruling that denies the government’s motion to dismiss or for summary judgment decides only that the taxpayer’s facts, if proved, could amount to reasonable cause. It is not a finding that they did. Tick the box to include those rulings; they are useful for pleading a refund suit, less so for predicting a result.
Can I cite a Tax Court summary opinion in a reasonable cause request?
You can describe it, but IRC 7463(b) says a summary opinion may not be treated as precedent for any other case. The IRS examiner or Appeals officer will weigh the facts, not the citation. Memorandum and regular opinions, circuit decisions and Boyle carry weight.
How were the excuse categories assigned?
By reading the reasonable cause passages of each opinion and tagging every excuse the taxpayer actually argued, using a fixed list of thirteen categories. Where an opinion rests on several facts the judgment is the editor’s; the holding field explains the court’s reasoning and the opinion controls.
Why does the same caption appear twice?
Some cases produced more than one decision, for example a circuit reversal followed by a Tax Court opinion on remand (Kaufman, Whitehouse Hotel). Each decision is a separate record with its own outcome.