Some data is collected about the package.
For example, the file program is run on each file in the package and the output is saved in the file-info file in the lab. The checker scripts are run over the package and report any discovered policy violations or other errors. These scripts don't access the package contents directly, but use the collected data as input. This separation of the checker scripts from the unpacking tools and the data collector scripts makes it possible to run Lintian several times over a package without having to unpack the package each time. Furthermore, since it is sufficient to save the statistics files of each package in order to run the checks, one can store these files for all packages of the Debian archive if one wants to check the whole distribution several times.