sejmdiff

Methodology

How sejmdiff builds the history of an act: where the texts come from, how each version is made and what to keep in mind when reading it.

Where the texts come from

The ELI API of the Sejm gives the text of an act as announced, each consolidated text (tekst jednolity) published in the official journal, the list of acts that amend it and the dates their changes enter into force. The texts are read from the official HTML or PDF files. The same source gives the unified text (U) of the Chancellery of the Sejm, where an act has one.

Bills before the Sejm never take part in building a version: they are only previewed on the timeline. All sources are listed on the About page.

How a version is made

How the versions of an act follow each other An official text is followed by versions reconstructed from the instructions of the amending acts, each applied on the day its changes enter into force. The next official consolidated text is compared with the last reconstruction and is the start for the changes after it. The unified text of the Chancellery of the Sejm stands apart as an unofficial version. Official text original or consolidated text Amending acts instructions, e.g. “uchyla się pkt 3” Reconstructed versions one per amending act, applied on the day it enters into force Next consolidated text compared with the reconstruction; later changes are applied to it Unified text (unofficial) Chancellery of the Sejm; a separate version, never a base for others
  1. The start is an official text: the act as announced, or a consolidated text.
  2. For each amending act that the text does not include yet, sejmdiff reads its instructions, such as „art. 5 otrzymuje brzmienie…” or „uchyla się pkt 3”, finds the place each one points to and applies it.
  3. Changes are applied in order of entry into force. The dates come from the ELI API; where the closing article of an amending act gives some provisions another date, that date is used for them. Each amending act and date gives one reconstructed version.
  4. If an amending act was itself amended before its change took effect, the change is applied in the wording in force on that day, where its amendments can be read and applied; elsewhere the wording as first published is used.
  5. The next consolidated text is shown as a version of its own. The reconstruction before it is compared with it, and the amending acts it already covers are not applied again. Later amendments are applied to the consolidated text, not to the reconstruction.
  6. The unified text of the Chancellery of the Sejm, if the act has one, is added as an unofficial version at its date. Later versions do not build on it.

Reading the timeline

Original text, Consolidated text
Official versions.
Reconstructed
Made by software from one amending act; not an official text.
Unified text (unofficial)
Prepared by the Chancellery of the Sejm for information; not legally binding.
Applied x of y instructions
Only some of the instructions amending the act could be applied, so the text may lack the other changes.
Amends the amending act
An act changed the amending act before its change took effect. The warning under it says how many of those changes could be applied.
Reconstruction matches this text: x
Shown on a consolidated text: how closely, line by line, the reconstruction before it agrees with it.

Limits

A text read from a PDF file can contain reading errors, and an instruction can be written in a way the software cannot apply; the version then lacks that change.

Changes that are never applied and other gaps are listed under Gaps and limits on the About page. How closely reconstructions match the official consolidated texts is shown on the Validation page.

sejmdiff is not an official source. Only the text published in Dziennik Ustaw / Monitor Polski is legally binding.