§ 20-5-306 — Simultaneous proceedings

(a) Except as otherwise provided in W.S. 20-5-304, a court
of this state may not exercise its jurisdiction under this
article if, at the time of the commencement of the proceeding, a
proceeding concerning the custody of the child has been
commenced in a court of another state having jurisdiction
substantially in conformity with this act, unless the proceeding
has been terminated or is stayed by the court of the other state
because a court of this state is a more convenient forum under a
provision of law from that state that is in substantial
conformity with W.S. 20-5-307.
(b) Except as otherwise provided in W.S. 20-5-304, a court
of this state, before hearing a child custody proceeding, shall
examine the court documents and other information supplied by
the parties pursuant to W.S. 20-5-309. If the court determines
that a child custody proceeding has been commenced in a court in
another state having jurisdiction substantially in accordance
with this act, the court of this state shall stay its proceeding
and communicate with the court of the other state. If the court
of the state having jurisdiction under the laws of that state in
substantial conformity with this act does not determine that the
court of this state is a more appropriate forum, the court of
this state shall dismiss the proceeding.
(c) In a proceeding to modify a child custody
determination, a court of this state shall determine whether a
proceeding to enforce the determination has been commenced in
another state. If a proceeding to enforce a child custody
determination has been commenced in another state, the court
may:
(i) Stay the proceeding for modification pending the
entry of an order of a court of the other state enforcing,
staying, denying or dismissing the proceeding for enforcement;
(ii) Enjoin the parties from continuing with the
proceeding for enforcement; or
(iii) Proceed with the modification under conditions
it considers appropriate.