Riverbend mayor, one machine's readings altered: evidence account

The contest

Title: Riverbend mayor, one machine's readings altered

Candidates: Ames, Bell, Cruz.

Records in this count: 60.

Ballot file: comparison-altered-machine

Source: Synthetic committed CVRs. No real election was counted.

Sixty ballots, twenty to a precinct, one reading machine to a precinct. The papers hold Ames 22, Bell 28, Cruz 10. reader-3 recorded ten of its Bell papers as Ames, so the machine readings report Ames 32, Bell 18, Cruz 10. Each row is one physical ballot; `paper` is present only where the paper differs from the machine reading. This is a fixture, not a sealed container.

Where the records sat:

One stack of 60 records. There is no ballot manifest of sealed containers.

No container custody was supplied.

What was configured

Configuration version: comparison-failed-software-check-plurality-v1-under-ranked-pairs.

Configuration fingerprint (SHA-256): 2b65b1b66f35279425f5ea9b3c937a2ff5e2bd9d8cb9d4162e07bcab73e07c0d.

Counting rule: ranked pairs.

Ballot rules used: Two or more marks at one rank end the ballot there; 2 ranks in a row left blank end the ballot; a candidate marked again lower down counts as a rank left blank.

Ballot file: comparison-altered-machine. A third party with this file can rerun the count.

Audit: none. No seed was used.

Configured audit risk limit: 10%.

Plain-language configuration (check against statute intent):

Configuration version: comparison-failed-software-check-plurality-v1-under-ranked-pairs

Fingerprint (SHA-256): 2b65b1b66f35279425f5ea9b3c937a2ff5e2bd9d8cb9d4162e07bcab73e07c0d

Election: Riverbend mayor, one machine failed its software check, counted under ranked pairs (Tideman)

Voting opens: 2026-10-23T08:00:00.000Z.

Voting closes: 2026-10-23T14:00:00.000Z.

A demonstration configuration over committed fixture records, counting the same ballots under another rule. No audit ran under it, and no real election was counted under it.

Contests and candidates:

Riverbend mayor, one machine failed its software check (mayor): Ames; Bell; Cruz.

Counting rule: ranked pairs (Tideman).

Tiebreak: not used under this counting rule.

Ballot rules (how marks become a ranking):

Two or more marks at one rank: the ballot counts up to that rank and no further.

A candidate marked again lower down: that rank counts as a rank left blank.

2 ranks in a row left blank: the ballot counts up to there and no further.

A mark for anyone not on the ballot: a mark, so the rank is not blank, but never a vote.

Audit risk limit: 10%. A risk-limiting audit that runs under this configuration stops when the sample confirms the outcome at that limit, or sends the contest to a full hand count.

How a ballot is counted and how an audit stops are fixed by this version. Changing any of the lines above requires a new version id.

The count

What follows is the counting account under ranked pairs, including every intermediate step.

What was counted

Ballots in this count: 60.

Ballots from: Synthetic committed CVRs. No real election was counted.

Sixty ballots, twenty to a precinct, one reading machine to a precinct. The papers hold Ames 22, Bell 28, Cruz 10. reader-3 recorded ten of its Bell papers as Ames, so the machine readings report Ames 32, Bell 18, Cruz 10. Each row is one physical ballot; `paper` is present only where the paper differs from the machine reading. This is a fixture, not a sealed container.

How the marks on a ballot were read:

Two or more marks at one rank: the ballot counts up to that rank and no further.

A candidate marked again lower down: that rank counts as a rank left blank.

2 ranks in a row left blank: the ballot counts up to there and no further.

A mark for anyone not on the ballot: a mark, so the rank is not blank, but never a vote.

The rankings the ballots form, and how many ballots form each. A candidate a ranking does not name is ranked last on those ballots.

Head to head

Every candidate is set against every other. A ballot counts in a matchup when it ranks one of the two above the other. A candidate a ballot never ranks is ranked last on that ballot, tied with every other candidate it never ranks, so such a ballot has no preference between them.

Ranked pairs

Sort pairwise victories from strongest margin to weakest. Lock each victory in order unless it would close a cycle with victories already locked. Equal-strength victories are considered together, and any of them that would sit on a cycle is skipped.

Scores are finishing ranks from the locked graph (higher is better).

Outcome

Ranked-pairs scores: Ames 3; Bell 2; Cruz 1.

Ames is elected under ranked pairs (Tideman): after locking the strongest victories that do not close a cycle, Ames finishes first.

Records with no mark, by contest and by machine

At the close of polls, the share of records with no mark in each contest, by contest and by machine. Leaving a contest blank is a voter's right; an outlier below is a question about the ballot or the machine, not a verdict.

The audit

No audit ran.

What was found

No audit ran, so there are no sample findings.

Custody: none supplied. No container custody chain was recorded or verified.

Why it stopped

Decision: no audit.

No audit ran.

Outcome status: preliminary. Software tallies stay preliminary until an audit on the record confirms them or a full hand count of the record replaces them.