Oklahoma’s jail mortality rate ranks second in nation Keaton Ross Oklahoma Watch Deaths in Oklahoma’s largest county jails have trended upward over the past decade, an indication that some inmates aren’t receiving adequate medical and mental health care. According to a Reuters News investigation published last October, 148 inmates housed in Oklahoma’s 11 largest county jails died from 2009 through 2019. The jails combined had an average annual mortality rate of 2.16 deaths per 1,000 inmates, the second highest in the nation behind West Virginia. The Oklahoma County Detention Center reported an especially high number of inmate deaths. From 2016 through 2019, the jail had 40 deaths and an average annual mortality rate of 4.77 deaths per 1,000 inmates. The national average is 1.46 deaths per 1,000 inmates.