HoC vs HoR difference

Theme 1

Democratic legitimacy of electoral boundaries

US 1

Both system use FPTP for lower chamber elections but the way electoral boundaries are drawn differs significantly.

In US, congressional district boundaries are drawn by state legislatures, which often work under party control.

This produce partisan gerrymandering that can entrench legislative majorities regardless of vote share.

as illustrated by the texas redistricting 2020, which created 2 safe GOP seats to texas republicans by packing and cracking dem voters in urban districts.

the result is that US boundary drawing raises democratic legitimacy concerns that UK’s independent commission model is specifically designed to prevent.

UK 1

In UK, independent boundary commissions draw all 650 parliamentary constituencies free from party control.  

The most recent review delivered the 2024 election map.  

Mini 1

Structural theory:  
how boundaries are drawn is set by formal institutional design.  

In US, state legislatures draw congressional districts under party control, which produce gerrymandering and recurring litigation over racial vote dilution.  
in UK, independent boundary commission draw all parliamentary constituencies free from party input.  
Difference:  

Politicised boundary drawing (US) vs independent commission led drawing (UK) 

Theme 2

Legislative dominance within bicameralism

US 2

In the US, Senate has equal legislative power to the House on most legislations.  
The upper chamber can block amend or reject house passed bills indefinitely.  

Failure of skinny repeal (2017) when 3 republican senators John Mccain Susan Collins and Lisa Murkowski joined dem to vote it down 51-49, despite house passing the American healthcare act AHCA, repeal and replace bill for the ACA 2010.

UK 2

UK parliament Act 1911, 1949 limit the house of lords to one year delay on most bills and money bills pass within one month. 

UK commons is therefore considerably more dominant within its bicameral system than the US house. 

-passage of Public offences (amendment) Act 2000

Mini 2

Structural theory:  

Because how dominant each chamber is within its bicameral system is set by statute or constitution.  
in UK, parliament Acts cap lords delay at one year, making the lords subordinate.  
In US, Article I makes Senate consent essential and 60 vote cloture threshold gives the filibuster a structural veto over most legislation.  

Difference:  

Commons is dominant by statute (UK) vs House is co-equal with the Senate by constitution.  

Theme 3

Term length and frequency of elections 

US3

US rep serve 2 year terms, which crate more frequent accountability but also a permanent campaigning environment.  

UK 3

UK MPs serve for up to 5 years.  
The dissolutions and calling of parliament Act 2022 returned the power to call elections to the PM, replacing the fixed term parliament Act 2011.  

Mini 3

The structural difference in term length shapes legislative behaviour.  

Rational theory:  

Because term length determines how often legislators have to make electoral calculations.  
US rep weigh every vote against a 2 year primary and general election, which encourage them to prioritise constituency responsiveness over party line voting.  
UK MPs calculate on a larger 4-5 year cycle, which makes complying with the whip the more rational short term choice.  

Difference: frequent US electoral horizons encourage constituent responsiveness, longer UK horizons encourage whip compliance.