What are the precise differences between various forms of notices for raising matters of public importance?

Rajya Sabha offers multiple procedural devices for raising matters of public importance, each with distinct purposes, formats, and outcomes. Zero Hour submissions raise urgent current matters with no formal follow-up, limited to three minutes speaking time, selected through daily ballot. Special Mentions under Rule 180A require ministerial responses within three months and must be read verbatim as approved.

Calling Attention notices under Rule 180 draw attention to urgent matters of public importance, allowing the Minister to make a statement followed by brief clarifications. Short Duration Discussions under Rule 176 allow more substantive two-and-a-half hour debates on matters of urgent public importance without formal motions or voting.

Adjournment Motions (Rule 56) interrupt normal business to discuss a definite matter of urgent public importance with the consent of the Speaker - these are rare and require meeting strict criteria of urgency, public importance, and ministerial responsibility. Rule 267 motions to suspend rules are even more exceptional, requiring demonstration that no other procedure is adequate.

For Zero Hour, Rule 5.1(i) establishes submissions must be made "between 12 Noon till 05.00 P.M. on the previous day," while Rule 5.1(v) specifies "Fifteen notices selected through the ballot will be allowed to be raised." For Special Mentions, Rule 180A states members may "mention matters of urgent public importance" with "the permission of the Chairman." Calling Attention notices under Rule 180 allow a member to "call the attention of a Minister to any matter of urgent public importance," while Short Duration Discussions under Rule 176 permit discussion "on a matter of urgent public importance" for "not exceeding two and a half hours."