  We show that every right-angled Artin group AG defined by a graph G of finite
chromatic number is poly-free with poly-free length bounded between the clique
number and the chromatic number of G. Further, a characterization of all
right-angled Artin groups of poly-free length 2 is given, namely the group AG
has poly-free length 2 if and only if there exists an independent set of
vertices D in G such that every cycle in G meets D at least twice. Finally, it
is shown that AG is a semidirect product of 2 free groups of finite rank if and
only if G is a finite tree or a finite complete bipartite graph. All of the
proofs of the existence of poly-free structures are constructive.
