An entity or an individual, whether acting on his or her own behalf or as an agent of another entity not permitted to appeal, may be permitted to participate as a party if the presiding official finds that:

The final decision could directly and adversely affect it or the class it represents;

The individual or entity may contribute materially to the disposition of the proceedings;

The individual's or the entity's interest is not adequately represented by existing parties; and

Intervention would not unfairly prejudice existing parties or delay resolution of the proceeding.

A tribe with jurisdiction over the lands on which there is a gaming operation that is the subject of a proceeding under this part may intervene as a matter of right if the tribe is not already a party.

A motion to intervene shall be submitted to the presiding official within 10 days of the notice of appeal. The motion shall be filed with the presiding official and served on each person who has been made a party at the time of filing. The motion shall state succinctly:

The moving party's interest in the proceeding;

How his or her participation as a party will contribute materially to the disposition of the proceeding;

Who will appear for the moving party;

The issues on which the moving party seeks to participate; and

Whether the moving party seeks to present witnesses.

Objections to the motion must be filed by any party within 10 days after service of the motion.

A reply brief to the brief in opposition may be filed within 5 days of service of the brief in opposition.

When motions to intervene are made by individuals or groups with common interests, the presiding official may request all such movants to designate a single representative, or he or she may recognize one or more movants.

The presiding official shall give each movant and party written notice of his or her decision on the motion. For each motion granted, the presiding official shall provide a brief statement of the reason(s) for the decision. If the motion is denied, the presiding official shall briefly state the ground(s) for denial. The presiding official may allow the movant to participate as amicus curiae, if appropriate.