Where the data comes from, and how we handle it

This page explains where our data comes from, how we process it, and the rules we hold ourselves to. It grows as the site does. Each new kind of data gets its method written up here before it goes live.

The sources

We build directly on the UK Parliament's own public data services: the Members, Commons Votes, Lords Votes, Bills, Hansard and related APIs, together with official sources for constituency boundaries and postcode lookups. We do not copy other data sites; we go to the same source they do. Full attribution is on our licence page.

How often it updates

The record is refreshed automatically on a schedule, not by hand. Every data page carries a "last updated" line so you can see how current it is. The official debate transcript (Hansard) is published with a short delay at source, and we show it as soon as it is available.

How we treat figures we calculate

Where we work something out, such as a majority, an attendance rate, or how often an MP votes with their party, we show the plain figure and link to the records it came from. We keep the language factual and we do not dress a vote up as loyal, rebellious, good or bad. If a number appears on this site, you will always be able to trace it back to the source.

Party loyalty, rebellions and alignment

Parliament does not publish how MPs are whipped, so any loyalty or rebellion figure anywhere is an interpretation of the recorded votes. Here is exactly how we do it:

• The party line in a division is the side (Aye or No) that the majority of that party's members voted for in that division. It is recalculated for every vote and says nothing about the formal whip.
• A rebellion is a recorded Aye or No vote against that majority. Absences, abstentions and tellers never count. A member's party is taken as it was on the day of the vote, so a member who later changed party is scored against the party they sat for at the time.
• Free votes. When a party splits at least 75/25 in a division, it had no meaningful line that day, usually because the vote was unwhipped (a conscience vote such as assisted dying). We do not count anyone's vote in that party as a rebellion in those divisions, and we label the division as a likely free vote. Some sites count these as rebellions; we think that overstates defiance.
• Exclusions. The Speaker and independents have no party line and are not scored. We show no loyalty percentage for members with fewer than 50 comparable votes, because small samples mislead.
• Voting alignment between two MPs is the share of divisions where both cast a comparable Aye or No and chose the same side, shown only when they share at least 50 such votes.
• Participation is the share of divisions a member was recorded in that they actually voted in. It cannot distinguish a deliberate abstention from an absence at Westminster; Holyrood records abstentions explicitly, so our Scottish Parliament pages show them as their own figure.
• Topic groupings ("votes by issue") are our own labels, applied by matching division titles against a hand-maintained list of keywords. They are deliberately broad and are not official Parliament categories.

These derived figures are recomputed every night from the official voting records we hold, and every page that shows them links back here.

Corrections

Accuracy matters more than speed here. These are real, named people and the public record. If you spot something wrong, tell us and we will check it against the official source and fix it promptly. A note of any material correction stays with the affected page. Contact details for corrections will be published here as the site opens up.