Does the duration of doctoral and postdoctoral phase *always* matter for a W1 position in Germany? Junior professorships in Germany are claimed to have, essentially, restrictions in terms of the speed of progress: https://de.wikipedia.org/wiki/Juniorprofessur says 


  In principle the employment before the graduation and as postdoc altogether must (in some federal states: may) amount to not more than six, in the medicine not more than nine years, whereby the regulations differ among the federal states.


The above text (due to "in principle", whatever it might mean) is somewhat imprecise. 

1) Which laws/regulations, if any, improse such a restriction in the 16 federal states? (@Roland pointed to http://de.wikipedia.org/wiki/Landeshochschulgesetz, but I failed to find the corresponding passages, for Bavaria, Bremen, Hessen, NRW, and Saxony-Anhalt. Moreover, some passages in the corresponding laws say "bleiben außer Betracht". E.g., if for Hamburg we see "Behinderungsbedingte Überschreitungen dieser Zeiträume bleiben außer Betracht.", does it mean that impaired applicants get an extension?)

2) In practice, have there been any junior professorships without restrictions concerning the duration of the prior academic career?
There are two different regulations applying here:

On the federal level, it is mandated that barring exceptional circumstances, a researcher is not supposed to exceed 12 years in total on temporary German university positions. Since a typical duration for a junior professorship is 6 years, that would mean no more than 6 years of temporary employment at German universities before that. This rule does not apply to certain external funding sources inside Germany, and not at all to positions held outside of Germany. Thus, this imposes a rather tight deadline on people intending to have their whole career in Germany, but does not matter much for those who are doing part of their career elsewhere.

In addition, each state has their own law describing who exactly is eligible to become a junior professor. For example, in Hamburg one may not have more than 3 years of postdoc experience. Since there are 16 states, listing all laws is not feasible for me. Also, do not count on this information being listed explicitly in job adverts.