The purpose of parliamentary procedure is for the assembly to conduct its businesses in the most efficient way possible while considering the rights of its members.
The minority have certain rights that only a supermajority, such as a two-thirds vote, can rule over. Such rights include introducing new business and speaking in debate.
Member rights
Members have the right to attend meetings, speak in debate, and vote. A member cannot be individually deprived of those rights except through disciplinary procedures. On the other hand, nonmembers have none of these rights and the assembly can exclude any or all of them from the proceedings. Members have the right to know what they are deciding on. The assembly acts on fairness and good faith. All members are treated equally. Members are expected to be of honorable character.
Absentee rights
Certain actions require previous notice, which protects the rights of absentees. This includes notice of the meetings. There also needs to be a quorum, or the minimum number of members to be present at a meeting.
One question at a time
Only one motion can be pending at a time. According to Robert's Rules of OrderNewly Revised, this rule is considered to be a "fundamental principle of parliamentary law".
Each member has a vote and each vote is weighted equally. According to RONR, this rule is considered to be a "fundamental principle of parliamentary law". Exceptions to this rule, such as cumulative voting, must be expressly provided for in the organization's rules.
Only members present can vote
The decisions made by members present at a meeting are the official acts in the name of the organization. According to RONR, this rule is considered to be a "fundamental principle of parliamentary law". Exceptions for absentee voting would have to be expressly provided for in the organization's rules. Nonmembers are not allowed to vote.
The group must have the authority to take the actions it purports to take. To be valid, any action or decision of a body must not violate any applicable law or constitutional provision. Also, actions cannot be in conflict with a decision previously made unless that action is rescinded or amended. The body can change the rules it wants to follow as long as it follows the rules for making such changes.