This paper combines two ideas:
(i) That the Lewisian best system analysis of lawhood (BSA) can cope with laws that have exceptions (cf. Braddon-Mitchell 2001, Schrenk 2007).
(ii) That a BSA can be executed not only on the mosaic of perfectly natural properties but also on any set of special science properties (cf., inter alia, Schrenk 2007 & 2008, Cohen & Callender 2009 & 2010).
Bringing together (i) and (ii) results in an analysis of special science ceteris paribus laws
