Last night, the Conservatives won a vote on cuttiing tax credits by £4.4bn - which could amount to a cut of £1,000 a year for three million families, according to Labour's shadow chief secretary to the Treasury, Seema Malhotra.

Now, we'd expect the Tories to win, as they have a majority of 12, meaning if every other party in the Commons – Labour, the SNP, the Northern Irish parties, the Liberal Democrats, and the lone Green MP – votes against the government, and just two Tory MPs (David Davis, and Stephen McPartland) rebelled, they’d still get the vote through. (Six Conservative MPs need to rebel for the Tories to be defeated.) But instead the Tories won with a majority of 35, sparking anger and confusion on social media. What happened?

First things first: although the government technically has a majority of 12, in reality, they have a majority of 16. The Speaker, John Bercow, and his deputies, don't vote, the net effect of which is to reduce the number of anti-Conservative MPs. And Sinn Féin, who have four MPs in Northern Ireland, don't take their seats in Parliament.

Equally importantly, plans to cut tax credits are only at second reading - read more about how a bill becomes law here - when the numbers in defeat are less important than during amendments or at committee stage. (When laws come up before the courts, judges take into account points made in debate at this stage and the "strength of feeling" on an issue. So, if, say, the Assisted Dying Bill had become law, but large numbers had voted for stronger safeguards, judges might take a more cautious reading of the law than if it had sailed through with an overwhelming majority.)

At any given time, some MPs will be absent due to illness, care duties to elderly relatives or small children, or foreign trips. Government ministers or oppostion frontbenchers may have appointments they can't miss. The pairing system means that if, say, a Conservative MP is on maternity leave, a Labour MP just won't turn up. At present, the Labour MP Rachel Reeves is on maternity leave, while Thanggam Debbonaire, another Labour MP, is undergoing chemotherapy, meaning both have been absent from key votes in recent days. A party's "whips" are meant to make sure that the numbers add up.

(This, incidentally, explains what John Rentoul calls "the first rule" of political journalism: "Don't do a Top 10 Laziest MPs. You always include people dying of cancer." )

And because the Conservatives have a majority of 12, Labour whips, if they've done the numbers right, will often let Labour MPs go home early, to see their families or work in the constituencies or lie in bed with a cold. (As will the Conservatives.) It tends only to be narrow votes - or government defeats, like on the referendum and the plans to kick out John Bercow - that are fully attended.

In this instance, Labour's Whips' office, like Labour's frontbench, is still under construction, perhaps accounting for the mess-up. Tory whips, fearing a bigger rebellion than arrived, ensured that their MPs voted in greater numbers, suspended pairing, and called in George Osborne to reassure uneasy backbenchers, which is why the bigger victory happened.

Below is the full list of ayes, noes and absentees:

Ayes

Adams, Nigel

Afriyie, Adam

Aldous, Peter

Allan, Lucy

Allen, Heidi

Amess, Sir David

Andrew, Stuart

Ansell, Caroline

Argar, Edward

Atkins, Victoria

Bacon, Mr Richard

Baker, Mr Steve

Baldwin, Harriett

Barclay, Stephen

Baron, Mr John

Barwell, Gavin

Bebb, Guto

Bellingham, Mr Henry

Benyon, Richard

Beresford, Sir Paul

Berry, Jake

Berry, James

Bingham, Andrew

Blackman, Bob

Blackwood, Nicola

Blunt, Crispin

Boles, Nick

Bone, Mr Peter

Borwick, Victoria

Bottomley, Sir Peter

Bradley, Karen

Brady, Mr Graham

Brazier, Mr Julian

Bridgen, Andrew

Brine, Steve

Brokenshire, rh James

Bruce, Fiona

Buckland, Robert

Burns, Conor

Burns, rh Sir Simon

Burrowes, Mr David

Burt, rh Alistair

Cairns, Alun

Cameron, rh Mr David

Carmichael, Neil

Carswell, Mr Douglas

Cartlidge, James

Cash, Sir William

Caulfield, Maria

Chalk, Alex

Chishti, Rehman

Chope, Mr Christopher

Churchill, Jo

Clark, rh Greg

Clarke, rh Mr Kenneth

Cleverly, James

Clifton-Brown, Geoffrey

Coffey, Dr Thérèse

Collins, Damian

Colvile, Oliver

Costa, Alberto

Cox, Mr Geoffrey

Crabb, rh Stephen

Crouch, Tracey

Davies, Byron

Davies, Chris

Davies, David T. C.

Davies, Glyn

Davies, Dr James

Davies, Mims

Davies, Philip

Dinenage, Caroline

Djanogly, Mr Jonathan

Donelan, Michelle

Dorries, Nadine

Double, Steve

Dowden, Oliver

Doyle-Price, Jackie

Drax, Richard

Drummond, Mrs Flick

Duddridge, James

Duncan, rh Sir Alan

Duncan Smith, rh Mr Iain

Dunne, Mr Philip

Ellis, Michael

Ellison, Jane

Ellwood, Mr Tobias

Elphicke, Charlie

Eustice, George

Evans, Graham

Evans, Mr Nigel

Evennett, rh Mr David

Fabricant, Michael

Fallon, rh Michael

Fernandes, Suella

Field, rh Mark

Foster, Kevin

Fox, rh Dr Liam

Francois, rh Mr Mark

Frazer, Lucy

Freeman, George

Freer, Mike

Fuller, Richard

Fysh, Marcus

Gale, Sir Roger

Garnier, rh Sir Edward

Garnier, Mark

Gauke, Mr David

Ghani, Nusrat

Gibb, Mr Nick

Gillan, rh Mrs Cheryl

Glen, John

Goldsmith, Zac

Goodwill, Mr Robert

Gove, rh Michael

Graham, Richard

Grant, Mrs Helen

Gray, Mr James

Grayling, rh Chris

Green, Chris

Green, rh Damian

Greening, rh Justine

Grieve, rh Mr Dominic

Griffiths, Andrew

Gummer, Ben

Gyimah, Mr Sam

Halfon, rh Robert

Hall, Luke

Hammond, rh Mr Philip

Hammond, Stephen

Hancock, rh Matthew

Hands, rh Greg

Harper, rh Mr Mark

Harrington, Richard

Harris, Rebecca

Hart, Simon

Haselhurst, rh Sir Alan

Hayes, rh Mr John

Heald, Sir Oliver

Heappey, James

Heaton-Harris, Chris

Heaton-Jones, Peter

Henderson, Gordon

Herbert, rh Nick

Hermon, Lady

Hinds, Damian

Hoare, Simon

Hollingbery, George

Hollinrake, Kevin

Hollobone, Mr Philip

Holloway, Mr Adam

Hopkins, Kris

Howarth, Sir Gerald

Howell, John

Howlett, Ben

Huddleston, Nigel

Hunt, rh Mr Jeremy

Hurd, Mr Nick

Jackson, Mr Stewart

James, Margot

Javid, rh Sajid

Jayawardena, Mr Ranil

Jenkin, Mr Bernard

Jenkyns, Andrea

Jenrick, Robert

Johnson, Boris

Johnson, Gareth

Johnson, Joseph

Jones, Andrew

Jones, rh Mr David

Jones, Mr Marcus

Kawczynski, Daniel

Kennedy, Seema

Knight, rh Sir Greg

Knight, Julian

Kwarteng, Kwasi

Lancaster, Mark

Latham, Pauline

Leadsom, Andrea

Lee, Dr Phillip

Lefroy, Jeremy

Leigh, Sir Edward

Leslie, Charlotte

Letwin, rh Mr Oliver

Lewis, Brandon

Lewis, rh Dr Julian

Liddell-Grainger, Mr Ian

Lidington, rh Mr David

Lilley, rh Mr Peter

Lopresti, Jack

Lord, Jonathan

Loughton, Tim

Lumley, Karen

Mackinlay, Craig

Mackintosh, David

Main, Mrs Anne

Mak, Mr Alan

Malthouse, Kit

Mann, Scott

Mathias, Dr Tania

May, rh Mrs Theresa

Maynard, Paul

McCartney, Jason

McCartney, Karl

McLoughlin, rh Mr Patrick

Menzies, Mark

Mercer, Johnny

Merriman, Huw

Metcalfe, Stephen

Miller, rh Mrs Maria

Milling, Amanda

Mills, Nigel

Milton, rh Anne

Mitchell, rh Mr Andrew

Mordaunt, Penny

Morgan, rh Nicky

Morris, Anne Marie

Morris, David

Morris, James

Morton, Wendy

Mowat, David

Mundell, rh David

Murray, Mrs Sheryll

Murrison, Dr Andrew

Neill, Robert

Nokes, Caroline

Norman, Jesse

Nuttall, Mr David

Offord, Dr Matthew

Opperman, Guy

Osborne, rh Mr George

Parish, Neil

Patel, rh Priti

Paterson, rh Mr Owen

Pawsey, Mark

Penning, rh Mike

Penrose, John

Perry, Claire

Phillips, Stephen

Philp, Chris

Pincher, Christopher

Poulter, Dr Daniel

Pow, Rebecca

Prentis, Victoria

Prisk, Mr Mark

Pritchard, Mark

Pursglove, Tom

Quin, Jeremy

Quince, Will

Raab, Mr Dominic

Redwood, rh John

Rees-Mogg, Mr Jacob

Robertson, Mr Laurence

Robinson, Mary

Rosindell, Andrew

Rudd, rh Amber

Rutley, David

Sandbach, Antoinette

Scully, Paul

Selous, Andrew

Shapps, rh Grant

Sharma, Alok

Shelbrooke, Alec

Simpson, rh Mr Keith

Skidmore, Chris

Smith, Chloe

Smith, Henry

Smith, Julian

Smith, Royston

Soames, rh Sir Nicholas

Solloway, Amanda

Soubry, rh Anna

Spelman, rh Mrs Caroline

Spencer, Mark

Stephenson, Andrew

Stevenson, John

Stewart, Bob

Stewart, Iain

Stewart, Rory

Streeter, Mr Gary

Stride, Mel

Stuart, Graham

Sturdy, Julian

Sunak, Rishi

Swayne, rh Mr Desmond

Swire, rh Mr Hugo

Syms, Mr Robert

Thomas, Derek

Throup, Maggie

Timpson, Edward

Tolhurst, Kelly

Tomlinson, Justin

Tomlinson, Michael

Tracey, Craig

Tredinnick, David

Trevelyan, Mrs Anne-Marie

Truss, rh Elizabeth

Tugendhat, Tom

Turner, Mr Andrew

Tyrie, rh Mr Andrew

Vaizey, Mr Edward

Vara, Mr Shailesh

Vickers, Martin

Villiers, rh Mrs Theresa

Walker, Mr Charles

Walker, Mr Robin

Wallace, Mr Ben

Warburton, David

Warman, Matt

Watkinson, Dame Angela

Wharton, James

Whately, Helen

Wheeler, Heather

White, Chris

Whittaker, Craig

Whittingdale, rh Mr John

Wiggin, Bill

Williams, Craig

Williamson, rh Gavin

Wilson, Mr Rob

Wollaston, Dr Sarah

Wood, Mike

Wragg, William

Wright, rh Jeremy

Zahawi, Nadhim

Tellers for the Ayes:

Simon Kirby

Sarah Newton



Noes

Abrahams, Debbie

Ahmed-Sheikh, Ms Tasmina

Alexander, Heidi

Ali, Rushanara

Allen, Mr Graham

Anderson, Mr David

Arkless, Richard

Ashworth, Jonathan

Austin, Ian

Bailey, Mr Adrian

Bardell, Hannah

Barron, rh Kevin

Beckett, rh Margaret

Benn, rh Hilary

Betts, Mr Clive

Black, Mhairi

Blackford, Ian

Blackman, Kirsty

Blackman-Woods, Dr Roberta

Blenkinsop, Tom

Blomfield, Paul

Boswell, Philip

Bradshaw, rh Mr Ben

Brennan, Kevin

Brock, Deidre

Brown, Alan

Brown, Lyn

Brown, rh Mr Nicholas

Bryant, Chris

Buck, Ms Karen

Burden, Richard

Burgon, Richard

Burnham, rh Andy

Butler, Dawn

Byrne, rh Liam

Cadbury, Ruth

Cameron, Dr Lisa

Campbell, rh Mr Alan

Campbell, Mr Gregory

Campbell, Mr Ronnie

Carmichael, rh Mr Alistair

Champion, Sarah

Chapman, Douglas

Chapman, Jenny

Cherry, Joanna

Clegg, rh Mr Nick

Clwyd, rh Ann

Coaker, Vernon

Coffey, Ann

Cooper, Julie

Cooper, Rosie

Cooper, rh Yvette

Corbyn, rh Jeremy

Cowan, Ronnie

Cox, Jo

Coyle, Neil

Crausby, Mr David

Crawley, Angela

Creagh, Mary

Creasy, Stella

Cruddas, Jon

Cryer, John

Cummins, Judith

Cunningham, Alex

Cunningham, Mr Jim

David, Wayne

Davies, Geraint

Davis, rh Mr David

De Piero, Gloria

Docherty, Martin John

Dodds, rh Mr Nigel

Donaldson, rh Mr Jeffrey M.

Donaldson, Stuart

Doughty, Stephen

Dowd, Jim

Dowd, Peter

Dromey, Jack

Dugher, Michael

Durkan, Mark

Eagle, Ms Angela

Eagle, Maria

Edwards, Jonathan

Efford, Clive

Elliott, Julie

Elliott, Tom

Esterson, Bill

Evans, Chris

Farrelly, Paul

Farron, Tim

Fellows, Marion

Ferrier, Margaret

Field, rh Frank

Fitzpatrick, Jim

Flello, Robert

Fletcher, Colleen

Flint, rh Caroline

Flynn, Paul

Fovargue, Yvonne

Foxcroft, Vicky

Gapes, Mike

Gardiner, Barry

Gethins, Stephen

Gibson, Patricia

Glass, Pat

Glindon, Mary

Godsiff, Mr Roger

Goodman, Helen

Grady, Patrick

Grant, Peter

Gray, Neil

Green, Kate

Greenwood, Lilian

Greenwood, Margaret

Gwynne, Andrew

Haigh, Louise

Hanson, rh Mr David

Harman, rh Ms Harriet

Harpham, Harry

Harris, Carolyn

Hayes, Helen

Hayman, Sue

Healey, rh John

Hendrick, Mr Mark

Hendry, Drew

Hepburn, Mr Stephen

Hillier, Meg

Hodge, rh Dame Margaret

Hodgson, Mrs Sharon

Hoey, Kate

Hollern, Kate

Hopkins, Kelvin

Hosie, Stewart

Howarth, rh Mr George

Hunt, Tristram

Huq, Dr Rupa

Hussain, Imran

Irranca-Davies, Huw

Jarvis, Dan

Johnson, rh Alan

Johnson, Diana

Jones, Gerald

Jones, Graham

Jones, Helen

Jones, Mr Kevan

Jones, Susan Elan

Kane, Mike

Keeley, Barbara

Kendall, Liz

Kerevan, George

Kerr, Calum

Kinnock, Stephen

Kyle, Peter

Lamb, rh Norman

Lammy, rh Mr David

Lavery, Ian

Law, Chris

Leslie, Chris

Lewis, Clive

Long Bailey, Rebecca

Lucas, Caroline

Lucas, Ian C.

Lynch, Holly

MacNeil, Mr Angus Brendan

Mactaggart, rh Fiona

Madders, Justin

Mahmood, Mr Khalid

Mahmood, Shabana

Malhotra, Seema

Mann, John

Marris, Rob

Marsden, Mr Gordon

Maskell, Rachael

Matheson, Christian

McCabe, Steve

McCaig, Callum

McCarthy, Kerry

McDonagh, Siobhain

McDonald, Andy

McDonald, Stewart Malcolm

McDonald, Stuart C.

McDonnell, John

McFadden, rh Mr Pat

McGarry, Natalie

McGinn, Conor

McGovern, Alison

McInnes, Liz

McKinnell, Catherine

McLaughlin, Anne

McPartland, Stephen

Meacher, rh Mr Michael

Meale, Sir Alan

Mearns, Ian

Miliband, rh Edward

Monaghan, Carol

Monaghan, Dr Paul

Moon, Mrs Madeleine

Morden, Jessica

Morris, Grahame M.

Mulholland, Greg

Mullin, Roger

Murray, Ian

Newlands, Gavin

Nicolson, John

Onn, Melanie

Onwurah, Chi

Osamor, Kate

Oswald, Kirsten

Owen, Albert

Paisley, Ian

Paterson, Steven

Pearce, Teresa

Pennycook, Matthew

Perkins, Toby

Phillips, Jess

Phillipson, Bridget

Pound, Stephen

Powell, Lucy

Pugh, John

Qureshi, Yasmin

Rayner, Angela

Reed, Mr Jamie

Reed, Mr Steve

Rees, Christina

Reynolds, Emma

Reynolds, Jonathan

Rimmer, Marie

Ritchie, Ms Margaret

Robertson, rh Angus

Robinson, Gavin

Robinson, Mr Geoffrey

Rotheram, Steve

Ryan, rh Joan

Salmond, rh Alex

Saville Roberts, Liz

Shannon, Jim

Sharma, Mr Virendra

Sheerman, Mr Barry

Sheppard, Tommy

Sherriff, Paula

Shuker, Mr Gavin

Siddiq, Tulip

Simpson, David

Skinner, Mr Dennis

Slaughter, Andy

Smeeth, Ruth

Smith, rh Mr Andrew

Smith, Angela

Smith, Cat

Smith, Jeff

Smith, Nick

Smith, Owen

Smyth, Karin

Spellar, rh Mr John

Starmer, Keir

Stephens, Chris

Stevens, Jo

Streeting, Wes

Stringer, Graham

Stuart, rh Ms Gisela

Tami, Mark

Thewliss, Alison

Thomas, Mr Gareth

Thomas-Symonds, Nick

Thompson, Owen

Thomson, Michelle

Thornberry, Emily

Timms, rh Stephen

Trickett, Jon

Turley, Anna

Turner, Karl

Twigg, Derek

Twigg, Stephen

Umunna, Mr Chuka

Vaz, rh Keith

Vaz, Valerie

Watson, Mr Tom

Weir, Mike

West, Catherine

Whiteford, Dr Eilidh

Whitehead, Dr Alan

Whitford, Dr Philippa

Williams, Hywel

Williams, Mr Mark

Wilson, Corri

Winnick, Mr David

Winterton, rh Ms Rosie

Wishart, Pete

Woodcock, John

Wright, Mr Iain

Zeichner, Daniel



Absentees

Laing, Eleanor

Percy, Andrew

Pickles, Eric

Wilson, Sammy

Abbott, Diane

Danczuk, Simon

Debbonaire, Thangam

Engel, Natascha

Griffith, Nia

Hamilton, Fabian

Hoyle, Lindsay

Kaufman, Gerald

Khan, Sadiq

Lewell-Buck, Emma

Lewis, Ivan

Nandy, Lisa

Reeves, Rachel

Shah, Naz

Berger, Luciana

Ellman, Louise

Brake, Tom

McDonnell, Alasdair

Brady, Mickey

Doherty, Pat

Maskey, Paul

Molloy, Francie

Day, Martyn

McNally, John

O’Hara, Brendan

Bercow, John

Kinahan, Danny