Comment 22 for bug 108189

dpkg does not produce invalid .list files. Data gets corrupted by bad hardware (disk/memory/filesystem bugs) and after that dpkg complains about the corrupted data.

All those .list files are important. If one gets corrupted, you can remove it but you should immediately reinstall the corresponding package to regenerate it (apt-get --reinstall install <package>). The format of those files is easy, one filename per line and nothing else. If you see garbage, then it's corrupted.