The U.S. national prisoner census in 1922 found that 54.6% of county prisoners were sentenced prisoners.^ The report noted:
the city returns include large numbers of persons held in police stations awaiting trial or detained as witnesses, so that the proportion which sentenced prisoners represent of the total number reported is undoubtedly much smaller for the cities than for the counties.^
Taking the share of sentenced prisoners in city institutions to be much smaller than the share of sentenced prisoners in county prisons implies fewer sentenced prisoners in generic jails (county and city jails and workhouses, plus farms, stockades, and chain and road gangs) in 1922 than in 1910. For example, Cahalan et al (1987)’s Historical Correctional Statistics assumed that 46% were sentenced in forming a “high estimate” of the number of sentenced prisoners in city institutions. This estimate implies fewer sentenced prisoners in jail in 1922 than in 1910. A fall in the number of sentenced prisoners from 1910 to 1922 is highly unlikely. The allocation of prisoners in farms and chain gangs between state and local institutions in states like Georgia contributes uncertainty to that comparison. In any case, estimating the share of sentenced prisoners in city institutions to be “much smaller” than 55% is inconsistent with plausible prisoner statistical trends.
The census of 1880 indicated that 55% and 72% of prisoners in “county jails” and “city prisons,” respectively, were sentenced prisoners. The first figure is the same as that reported for county jails in 1922. We take the second figure as an estimate of the share of sentenced prisoners in “city jails and workhouses” in 1922. That figures implies 65% of prisoners in generic jails (penal institutions other than federal and state facilities) were sentenced prisoners.