With U.S. "baby boomers" now in the 52 to 70 age range, it shouldn't be surprising that there has been a graying of the nation's prison population.
What is surprising is that the population of inmates over age 55 is also increasing as is the number of people being sentenced to prison at age 55 and older.
That was the finding of a recent study analyzing two decades of prison demographics by E. Ann Carson, a statistician for the U.S. Bureau of Justice Statistics, and the bureau's former director, William J. Sabot.
The number of people 55 or older sentenced to more than a year in state prisons more than tripled from 1993 to 2013, from 26,300 in 1993 to 131,500 in 2013. Ten percent of state inmates are over 55, the study found.
So did the imprisonment rate for people over 55: from 49 per 100,000 U.S. residents in 1993 to 154 per 100,000 in 2013, according to the BJS study.
"Both the admission rate and year-end imprisonment rate for state prisoners age 55 or older increased from 1993 to 2013, which indicates that the aging U.S. resident population was not solely responsible for the growth in older offenders in prison," the report concluded.
The trend is reflected in the cohort of older prison inmates. Forty percent of state prisoners age 55 and older at the end of 2013 were admitted to prison when they were at least 55 and 60 percent turned 55 while serving time. About 40 percent of those inmates had been in prison for at least a decade, compared to 9 percent in 1993.
The study also found that 66 percent of state prisoners over 55 were in prison for violent offenses, ahead of any other age cohort. In 2013, the study continues, almost half of inmates over 55 were serving time for murder or some other violent crime, compared to 31 percent of inmates between the ages of 45 to 54 and 27 percent of inmates 35 to 44.
Going to prison after 55 has its own disadvantages. Sentencing guidelines include criminal histories in coming up with a suggested sentence. People sentenced at 55 or older are more likely to have criminal records and thus more likely to serve longer sentences.
The BJS study found that people over 55 sentenced for a violent crime could expect to serve an average of 15 years behind bars compared to 10 years for those incarcerated between 40 and 54 and about five years for those sentenced between ages 18 and 39.