LOS ANGELES, CA (Catholic Online) - Three decades of "historically unprecedented" build-up in the number of prisoners in the U.S. have led to a level of overcrowding that is now "taking a toll on the infrastructure" of the federal prison system, according to the research wing of the U.S. Congress.

"This is one of the major human rights problems within the United States, as many of the people caught up in the criminal justice system are low income, racial and ethnic minorities, often forgotten by society," Maria McFarland, deputy director for the U.S. program at Human Rights Watch says.

As a consequence of the imposition of very harsh sentencing policies, McFarland's office has begun seeing juveniles along with the very elderly being put in prison. "Last year, some 95,000 juveniles under 18 years of age were put in prison, and that doesn't count those in juvenile facilities," she noted.

"And between 2007 and 2011, the population of those over 64 grew by 94 times the rate of the regular population. Prisons clearly aren't equipped to take care of these aging people, and you have to question what threat they pose to society - and the justification for imprisoning them."

A growing number of these prisoners are being put away for charges related to immigration violations and weapons possession. The largest number is for rather petty drug offences. This is an approach that one of the report's authors, Nathan James warns is no longer useful in bringing down crime statistics.

"Research suggests that while incarceration did contribute to lower violent crime rates in the 1990s, there are declining marginal returns associated with ever increasing levels of incarceration," James notes.

A reason behind these startling figures is people that have been imprisoned for crimes in which there is a "high level of replacement."

Citing an example, James says that if a serial rapist is incarcerated, the judicial system has the power to prevent further sexual assaults by that offender, and it is likely that no one will take the offender's place.

"However, if a drug dealer is incarcerated, it is possible that someone will step in to take that person's place," James writes. "Therefore, no further crimes may be averted by incarcerating the individual."

The increase in prison population is also a result of a "get tough" approach on crime in the U.S., under which even nonviolent offenders are facing stiff prison sentences.

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