This paper deals with order identification for Markov chains with Markov
regime (MCMR) in the context of finite alphabets. We define the joint order
of a MCMR process in terms of the number k of states of the hidden Markov
chain and the memory m of the conditional Markov chain. We study the
properties of penalized maximum likelihood estimators for the unknown order
(k, m) of an observed MCMR process, relying on information theoretic
arguments. The novelty of our work relies in the joint estimation of two
structural parameters. Furthermore, the different models in competition are
not nested. In an asymptotic framework, we prove that a penalized maximum
likelihood estimator is strongly consistent without prior bounds on k and
m. We complement our theoretical work with a simulation study of its
behaviour. We also study numerically the behaviour of the BIC criterion. A
theoretical proof of its consistency seems to us presently out of reach for
MCMR, as such a result does not yet exist in the simpler case where m = 0
(that is for hidden Markov models).