The past year in Westminster by-elections
The last year has seen 6 parliamentary by-elections of which just two saw a change in the party holding the seat.
The first at Southend West wasn’t contested by the main parties and was filling the vacancy created by the murder of Sir David Amess.
Three – Birmingham Erdington, Chester and Stretford & Urmston – saw LAB defending solid majorities and there was very little betting.
The other two were on the same night in June when LAB took Wakefield from the Tories and the LDs Tiverton & Honiton. The former vacancy had been created by the resignation of the incumbent after being convicted of sexual assault. The latter vacancy followed the resignation of the sitting MP who had been accused of watching porn in the Commons Chamber.
None of the outcomes was ever in real doubt and I don’t think you could ever get longer than evens on the eventual winner.
So not a vintage year.