Tuesday, July 07, 2009

Steep decline in ex-offenders' probability of re-offending


After about 7.7 years after their last offense, if new Justice Department-funded research is correct, people with robbery convictions not only are much less likely to commit a new offense but thereafter are statistically less likely than the general population to commit new crimes. (Click on the chart to enlarge.) For burglars and those convicted of aggravated assault, the thresholds are even earlier (3.8 and 4.3 years, respectively).

This from a new reentry study focused on post-conviction employment I noticed via Doc Berman and Ted Gest. According to USA Today ("Study could ease concern over hiring ex-offenders," July 1):
A study funded by the Justice Department concludes that over time accused robbers, burglars and batterers pose no greater risk to employers than job candidates in the general population.

In a review of 88,000 arrestees in New York state, Carnegie Mellon University investigators found, for example, that after about 7 1/2 years the "hazard rate" for an 18-year-old first-time arrestee for robbery declined to the same rate as an 18-year-old in the general population. For 18-year-olds arrested for aggravated assault, it took about four years to reduce the risk.

Hazard rates are calculated based on the time the suspect remains free from re-arrest. The calculation also accounts for the fact that risk of arrest generally declines with age.

"We believe that our analysis provides the criminal justice community with the first scientific method for estimating how long is long enough for someone with a prior record" to no longer be considered a special risk, according to the study authored by Carnegie Mellon criminologist Alfred Blumstein. ...

The study focused on three offenses — robbery, burglary and aggravated assault — because they represented some of the largest sample numbers.

According to the National Institute of Justice, which created the graphic at the top of this post with data from Blumstein's study:
The probability of new arrests for first offenders declines with time from first arrest and eventually becomes lower than that of the general population. For those in the general population who were first arrested in 1980, the probability of being re-arrested decreased steadily the longer they stayed clean of further involvement with the criminal justice system. They can be compared to the general population, which mostly includes people never before arrested, as well as to those recently released from prison, who have a high risk of re-arrest. The probability of re-arrest of the 1980 arrestees who stayed clean eventually dropped below that of other people of the same age. For those first arrested for burglary at age 18 years, in 1980, the crossover occurred 3.8 years later at age 21.8. If their first arrest was for aggravated assault, crossover occurred 4.3 years later at age 22.3, and if the arrest was for robbery, it was 7.7 years later at age 25.7. The probability of re-arrest at each of these crossover points was slightly less than 10 percent.

24 comments:

Anonymous said...

What the study says is that they are less likely to get caught. In any line of work, you get more skilled the longer you do it.

DarthVelma said...

By including everyone who ever re-offended in their "general population" control group, of course they reached this conclusion. If they really wanted to know whether these folks are more "risky", they should have compared them only to folks in the same age group who were never convicted of a crime in the first place.

Gritsforbreakfast said...

2:04, that's very cute, but you assume a level of rank incompetence by police that I don't endorse. After all, they presumably get better at their jobs over time, too.

DarthVelma, I agree it'd be preferable to break them out, but I don't see how not doing so would bias or invalidate the conclusions. After 7.7 years, ex-offenders are providing downward pressure on the overall offense rate compared to the general population. The other thing to notice is that the rate for everybody gets lower as people get older.

I don't know why y'all would be defensive about this. Doesn't it mean they "learned their lesson," "the system worked," etc., etc.?

Schivo said...

Aha! Proof that prison works!

Don't change a thing!

Anonymous said...

Kind of makes those 15 to life sentences seem a little pointless.

Anonymous said...

@Shivo.. Ok as long as all of them actually did prison time... most people do Probation.. so to you I say ! AHa! Probation works, stop spending money on over-criminalization!

Anonymous said...

I couldn't find the link to the entire text for the study.

Anonymous said...

Schivo and Anon have a good point, it is not clear from the article why the risk of reoffending has gone down.

Nor is it clear what percentage actually make it to 7 1/2 years of being clean.

DarthVelma said...

Not really defensive, just pointing out what I see as a methodological issue. I do stats for a living...just me being pedantic. I do think it biases the data to include re-offenders in the control group. Their 100% re-offense rate is very different from the offense rate for those that were never convicted in the first place. Putting those two groups together as a control group yields an "average" offense rate that is not accurate for either group seperately. Just how biased the number is depends on what percentage of your population has multiple offenses.

I also think your point about re-offense rates decreasing with age is well taken and probably explains pretty much all the of results this study found.

DarthVelma said...

Oh, and honestly, the methodology issues in this study don't concern me all that much. This study really just seems to say something that most of us probably would have assumed - that the longer you go without getting trouble, the less likely you are to get in trouble. :)

I'll find the whole thing much more interesting when someone does the follow up work to find out what, if anything, is different about these folks who manage to stay on the straight and narrow long-term after they get out.

Anonymous said...

From personal experience, it is possible that some people do learn to change their ways. 2:04, you are very cynical in your viewpoint of humanity-try not to view people with such distrust.The glass doesn't have to be half empty, you know!There are many people who make a mistake in their youth, due to immaturity and poor judgement. Plenty of people choose to change their path, and become honest, law abiding citizens. Yes- it can happen!!

Soronel Haetir said...

Grits,

The police even as they become more experienced are still going to go for the low hanging fruit. And the cases that elected officials lose their jobs over, of course. Between those extremes would seem to be ample room for criminals that have learned how not to get caught.

Anonymous said...

That's good. Too bad it doesn't seem to be helping to curb immigrants from being unfairly deport from this county: http://lawblog.legalmatch.com/2009/05/14/most-removed-immigrants-not-criminals-data-shows/

Anonymous said...

Don't get too excited, it has nothing to do with the rehabilitation of prisoners. We are imprisoning an abundance of nonviolent young men,women and teenagers 18-26 year olds. Most of these folks want nothing more than to stay out once they get out contrary to the beliefs of most people, thanks to the media and television. we have become brainwashed to believe that most people in prison are bad people and that is just not the case. A lot of men and women in prison have children, husbands,and wives.

Anonymous said...

If I ask you whether you have ever decided something was not working in your life and if that decision lead to a change in your behaviors and/or views I suspect most people will say "yes".

If you can do change, is it reasonable to assume that an offender cannot change "once a criminal, always a criminal".

The transition involved in returning to the community from prison is one of the most difficult transitions any person can face. There are literally hundreds of barriers to successful reentry and many give up trying -- commit another crime or violate their parole -- and return to prison.

The good news in this study is that with support and reentry assistance people remain in the community and the longer they remain in the community the more likely they are to reestablish law abiding life styles, form a family and contribute constructively to society.

Any time we construct more barriers to rebuilding their lives we increase the pressure for them to reoffend or go back to prison both of which are policy failure - expensive failures.

This research was conducted by some of the most highly respected scholars in the field. It needs to be replicated to see if similar results can be obtained elsewhere. However, it offers hopeful direction for the formation of more effective policy.

Anonymous said...

The ones we get have been on probation a number of times and laughed at the requirements and often kept violating probation until we finally got them. When did they change their stripes and stop offending?

duaneh1 said...

I was convicted of crime back in '83 when a buddy and I swiped some hub caps. Served a few weeks in jail, been clean ever since. Not all criminals remain criminals

Gritsforbreakfast said...

FWIW, y'all, to me the study tells us that most of the volume in the system is dominated by repeaters but we cast the net so widely through overcriminalization that MOST people convicted of a crime have relatively low re-offense rates when viewed in aggregate (as mentioned by 7:50). What's more, even those repeaters usually age out of criminal behavior (or die) by their 40s, particularly for the three offense categories they studied.

To 3:07, I can't find a link to the full study and neither could Doc Berman. I'll keep looking and post it when I find it.

Anonymous said...

"The ones we get have been on probation a number of times and laughed at the requirements and often kept violating probation until we finally got them. When did they change their stripes and stop offending?"

I hold no fantasy that everyone that breaks a law cleans up and goes straight after their first time through the system. I do not think this study does that either. However, for you to make the grandiose statement that everyone going through the system laughed at the terms of probation and continuously violated is asinine.

I am sure a minority of probationers did violate, and those are the ones that NEED to be incarcerated, but to state that human beings cannot not make amends, learn from their mistakes, and go on to be productive citizens shows YOUR stripes at being an over-bearing member of the criminal justice population that has no understanding of human nature, nor understanding of people that made a single mistake and wanted to clean themselves up. Is that you Gov. Perry??

JSN said...

Irwin and others have studied how long criminal behavior lasts but such studies are complicated by persistent offenders that are mentally ill and/or are addicted to alcohol/drugs.

The usual summary statement is the offenders start to enter the juvenile justice system in large numbers at about age 14 and the peak age for offending is in the middle twenties.

This study is of interest because the sample size is so large and the authors set up a control group for comparison. It will be interesting to read the complete report when it becomes available.

Boyness said...

Anonymous said...

What the study says is that they are less likely to get caught. In any line of work, you get more skilled the longer you do it.

7/07/2009 02:04:00 PM
-----------------------------
What an ass and once again hiding behind the "anonymous" veil. COWARD!

Boyness said...

Bad news for TDCJ and the legislature. Better come up with some new felonies and tougher parole rules.

Anonymous said...

"Bad news for TDCJ and the legislature. Better come up with some new felonies and tougher parole rules"

I am sure there are some more Oysters or Shellfish that need to be protected...

:)

Eric Mayo said...

I take results from studies with a grain of salt. Ex-offenders who make up their minds not to offend again don't. Getting jobs and becoming contributing members of society is key. My name is Eric and I answer questions for ex-offenders and felons looking for jobs at my blog:

http://www.jailtojob.com/wordpress