Ontario Premier Doug Ford defended his government's plan to build many more jails, saying the billions in cost will be worth it.

Ontario's jails are well over capacity and the overcrowding has been worsening for years under Ford's tenure as premier.

The province plans to add upward of 6,000 new jail beds by 2050, government documents obtained by The Canadian Press show.

About 80 per cent of inmates in provincial jails are awaiting trial and presumptively innocent. The provincial institutions hold people who are accused of a crime but not on bail, as well as those serving sentences of two years less a day. Inmates with longer sentences are housed in the federal prison system.