The McNamara Cascade Protocol

Proportionality Without Compromise, Representation Without Waste.

Draft Model Bill & Drafting Instructions

Scottish Parliament (Electoral Reform) Bill

The McNamara Cascade Protocol (MCP)

Document: Explanatory Memorandum & Clauses
Legislative Competence: Scotland Act 1998 (s.12A / s.31A)
Chamber Capacity: 129 Seats Fixed
Succession Rule: Cascade Runner-Up (Zero By-Elections)

1. Constitutional & Legislative Competence

Devolution Framework: Under Section 3 and Section 4 of the Scotland Act 2016 (which devolved full electoral competence to Holyrood by amending the Scotland Act 1998), the Scottish Parliament possesses plenary legislative power over its voting system, seat allocation mechanics, nomination deposit structures, and vacancy succession.

Super-Majority Requirement: Under Section 31A of the Scotland Act 1998, any Bill modifying the parliamentary electoral system requires a two-thirds super-majority (at least 86 votes in the 129-seat chamber) at Stage 3 of the parliamentary process.

2. Draft Model Clauses

Clause 1: Interpretation & Core Definitions

  1. "Chamber Capacity (S)" means the total number of Members of the Scottish Parliament to be returned (129).
  2. "Registered Party List" means a list of candidates submitted by a registered political party under Part 2 of the Political Parties, Elections and Referendums Act 2000.
  3. "Individual Candidate" means any candidate standing in their personal capacity and not nominated on a registered party list.
  4. "Total Valid Ballots (V_raw)" means the aggregate sum of all valid list votes cast across Scotland.
  5. "Chief Counting Officer" means the returning officer responsible for certifying national list returns.

Clause 2: Quota Determination & Individual Candidate Capacity

  1. The Chief Counting Officer shall calculate the Base Quota (Q₀) = Total Valid Votes / Chamber Capacity (S).
  2. An Individual Candidate possesses a maximum statutory capacity of one seat (Capacity = 1).
  3. Where the votes polled by an Individual Candidate exceed the Base Quota (Votes > Q₀), the surplus votes (Votes − Q₀) shall be classified as non-transferable surplus and deducted from the active vote total.
  4. The Effective Vote Pool (V_eff) shall equal Total Valid Votes minus all Individual Candidate Surplus, and the Effective Quota (Q) shall equal V_eff / S.
  5. The fixed 1-seat quota percentage share is defined as (100 / S)% (being 0.77519% for 129 seats).

Clause 3: Stage 1 Allocation (Integer Quotas)

  1. For each Registered Party List, the number of Stage 1 seats allocated shall equal the whole integer quota quotient: ⌊Votes / Q⌋.
  2. For each Individual Candidate, the number of Stage 1 seats allocated shall equal one seat if Votes ≥ Q, and zero seats otherwise.
  3. The unused fractional vote remainder for each Registered Party List shall equal Votes − (Stage 1 Seats × Q) and be held in reserve.
  4. The total Stage 1 seats allocated shall be designated as S₁.
  5. The remaining unallocated seats shall constitute the Cascade Pool (R) = S − S₁.

Clause 4: Stage 2 Allocation (The Cascade Protocol)

  1. The Cascade Pool (R) shall be allocated primarily to maximize representation of qualifying cohorts unseated in Stage 1.
  2. The Chief Counting Officer shall compile the Unrepresented Entrant List (U), comprising all parties and individual candidates where Stage 1 Seats = 0 and Valid Votes > 0, arranged in descending order of total valid votes polled.
  3. Beginning with the highest-polling entrant on List U, one seat shall be allocated to each entrant in succession until all R seats are exhausted or all entrants on List U have received one seat.
  4. No entrant receiving zero valid votes shall be included on List U or awarded a parliamentary seat.

Clause 5: Stage 3 Allocation (Surplus Remainder Resolution)

  1. Where seats remain in the Cascade Pool after every eligible entrant on List U has been awarded one seat, the Chief Counting Officer shall initiate Stage 3 allocation.
  2. All Registered Party Lists that achieved one or more seats in Stage 1 shall be ranked in descending order of their unused fractional vote remainders calculated under Clause 3(3).
  3. Remaining surplus seats shall be allocated one-by-one in descending order down this list until the chamber reaches exactly 100% capacity (129 seats).
  4. Where two or more party lists possess identical fractional remainders, priority shall be awarded to the party list with the higher aggregate raw vote total.

Clause 6 & 7: Statutory Deadlocks, Casual Vacancies & Succession

  1. Statutory Deadlock (Ties): Where an exact equality of votes arises for the final Cascade seat, a mandatory recount shall occur. If still tied, the Chief Counting Officer shall resolve the tie by the drawing of lots under standard Scottish statutory election rules.
  2. Party List Vacancy: Where a Member returned via a Registered Party List vacates their seat (by death, resignation, or disqualification), the seat shall pass automatically to the next available candidate on that party’s registered list from the general election.
  3. Independent Vacancy or Exhausted List: Where an Individual Candidate vacates their seat, or where a Registered Party List has become exhausted with no further candidates available, the vacant seat shall pass automatically to the 1st Runner-Up (the next highest-polling unseated entrant) on the certified Stage 2 (Cascade) leaderboard from the general election.
  4. Abolition of By-Elections: Casual vacancies in the Scottish Parliament shall not under any circumstances trigger a by-election, ensuring the national proportional mandate of the general election remains permanent throughout the parliamentary term.

Clause 8: Nomination Deposits, Return Conditions & Proximity Relief

  1. Statutory Nomination Deposit: A nomination under Part 2 of this Act is valid only if there is deposited with the Chief Counting Officer—
    • (a) in the case of a Registered Party List, the sum of £5,000 (conferring nationwide multi-candidate ballot access for up to 129 candidates);
    • (b) in the case of an Individual Candidate, the sum of £2,500 (conferring nationwide single-candidate ballot access with a maximum capacity of one seat).
  2. Immediate Full Return (100%): The Chief Counting Officer shall return the deposited sum in full to the candidate or nominating agent no later than the next working day following the final declaration of the poll where the entrant is awarded one or more seats under Stage 1, Stage 2, or Stage 3.
  3. Standby Certification Rebate (50% Immediate + 50% Contingent):
    • (a) Where an entrant is not awarded a seat under subsection (2) but is certified among the top five (5) ranked unseated entrants on the official Stage 2 Cascade Standby List, the Chief Counting Officer shall immediately return 50% of the deposit (£2,500 for a party list; £1,250 for an individual candidate) in recognition of statutory standby status;
    • (b) The remaining 50% shall be held in escrow by the Scottish Parliamentary Corporate Body and returned in full if the entrant is subsequently allocated and accepts a parliamentary seat to fill a casual vacancy under Clause 6 or 7 during the parliamentary term.
  4. Proximity Relief (50% Return): Where an unseated entrant does not qualify for standby status under subsection (3) but polls a national vote total within 100 valid votes (or 0.005% of Total Valid Ballots) of the fifth-ranked entrant on the certified Stage 2 Standby List, the Chief Counting Officer shall return 50% of the deposit (£2,500 for a party list; £1,250 for an individual candidate) to account for statistical count variance.
  5. Forfeiture: All deposits or portions of deposits not qualifying for return under subsections (2), (3), or (4) shall be forfeited and transmitted to the Scottish Consolidated Fund to offset the administration costs of the national count, voter guides, and accessibility provisions.

3. Explanatory Memorandum for Parliamentary Counsel

Defect of Current AMS Framework

Regional list partitions artificially impose an effective electoral threshold of ~5.5% to 8.0%. Support distributed broadly across Scotland is discarded, creating high disproportionality and voter alienation.

Cascade Succession (Zero By-Elections)

By replacing distorted single-member by-elections with automatic succession down the verified Cascade leaderboard, the chamber preserves the exact mandate of the general election at zero cost to the taxpayer.

Individual Capacity Integrity

Unlike basic List-PR systems, MCP mathematically accounts for individual independent candidates by discounting surplus non-usable votes, preventing constitutional anomalies while preserving fair party competition.

Deposit Equity & National Access

The £5,000 / £2,500 deposit schedule reduces national ballot costs by over 87% compared to contesting 81 AMS contests, while the tiered Standby rebate and Proximity Relief eliminate arbitrary financial cliff-edges.