If the goal of a prison system is to prevent crime, provide justice and rehabilitate offenders, how close could we say we've come to that goal?

Curiosity contributor Bambi Turner took a look at the efficacy of the modern American prison system to see just how successful it was. Here's what she had to say.

Though both violent and property crime rates declined significantly between 1987 and 2007, the number of people imprisoned in the United States tripled. By 2011, more than one out of every 100 adults in the United States was confined to a jail or prison [sources: de Pugy, Pew Center on the States]. If one considers prevention and punishment the primary goals of a prison system, it would appear that the current one is quite effective -- for now. When one takes a longer view at imprisonment in America, it's also clear that the current system is completely unsustainable, and in dire need of reform.

Corrections processes cost the United States more than $50 billion each year, and the majority of this money goes to pay for prisons [source: Pew Center on the States]. Still, prison overcrowding is a common concern, particularly at the state level [source: Moore]. Unless the public is willing to spend more on new prisons or on additions to existing facilities, it will be difficult to maintain current mandatory sentencing policies with the prison system we have.

In an effort to develop more sustainable corrections practices, some jurisdictions have made rehabilitation a primary goal of the criminal justice system. In 2007, the state of Texas decided to invest in drug treatment programs and separate drug courts, which saved the state more than $200 million over the course of two years [source: Pew Center on the States]. Other states have focused on helping inmates successfully transition from prison back to the real world. While more than 40 percent of people released from prison will reoffend and end up back behind bars within three years, states like Oregon and Michigan that have invested heavily in prisoner transition programs have seen recidivism rates fall well below the national average [source: Pew Center on the States].

Privatization, or shifting control of prisons from the government to private businesses, represents a popular yet controversial strategy to improve the system. While proponents of privatization tout the increased efficiencies and cost savings of privately-run prisons, a study by the Arizona Department of Corrections found that private prisons actually cost up to $1,600 more per inmate to operate each year, despite the fact that they often "cherry pick" the healthiest and least costly inmates [source: Oppel]. Critics of privatization also point to problems that may arise when prisons are put into private hands, including issues related to quality, and the ethical dilemma involved in profiting from the imprisonment of human beings.