The three united parishes retained separate vestries and churchwardens. The parishes were governed by vestries and were subject to the Middlesex Quarter Sessions. There are also modern vestries north of the chancel and south of the tower. It comprised the chancel, an ambulatory, chapter house and vestries. The parish vestries were left with only church affairs to manage. Their borough councils replaced vestries and district boards as the second tier of local government. The seal depicted the emblems of the three parish vestries merged into the board. Both had been created in 1900, replacing parish vestries. The upper levels of the tribunes were designed as vestries. The vestries lie behind the altar of St John. A Victorian north aisle, vestries and south porch were added in the 1880s. The church and vestries were reluctant to bring boundaries up to date. The chapter house and new vestries were completed. This was built to seat 600 people, with school hall, vestries and classrooms. The larger vestries had two members and the City of London had three.