fwiw, Schwarzenegger is proposing using house arrest and ankle bracelet technology to get CA's least violent offenders out of our over-crowded prisons.

I and others have been able to show that the prison source neighborhoods tend to be low rent urban neighborhoods with high unemployment rates. The police get a lot of calls for service from such neighborhoods and they respond by increasing their patrols or putting in a substation and the police also take a professional interest in persons on probation and parole. All of these factors tend to increase the probability of arrest.

An arrested person who is unemployed and has a prior criminal record is more likely to be detained in jail than an employed person with no record. I think it is very likely that the high Black/White ratios for jail and prison inmates are established in the first 24 hours after arrest.

There is a very long list of sociological variables that might be important in explaining the high Black/White ratio for arrest rates. Blacks have higher unemployment rates,poverty rates, high school drop out rates, lower college graduation rates and median family income and they are more likely to be from a single parent family.

According to the newly released New York City Police Department report, "Radicalization in the West: The Homegrown Threat" (PDF) by Mitchell D. Silber and Arvin Bhatt Senior Intelligence Analysts NYPD Intelligence Division, prisons are "A Radicalizing Cauldron".

"Prisons can play a critical role in both triggering and reinforcing the radicalization process. The prison's isolated environment, ability to create a "captive audience" atmosphere, its absence of day-to-day distractions, and its large population of disaffected young men, makes it an excellent breeding ground for radicalization."

More: U.S. drug war prisons: "A Radicalizing Cauldron"

Mesh this assertion with America's world record prison population. Add to that the fact that alQaida has taught people to use prisons for recruiting. The Madrid train bombings were carried out by people wno met in prison and, using that networking structure put together the drugs used to fund and facilitate the operation.

Madrid bomb leader 'identified'
BBC News
1 April, 2004
The BBC's Katya Adler in Madrid says Spanish security officials now say they believe drug-trafficking played a significant role not only in financing the bombings but also in establishing relationships between key protagonists.

Media reports say Jamal Ahmidan, who has alleged links to al-Qaeda, was orginally recruited by Muslim radicals while serving a prison sentence in Morocco for drug-trafficking.

Holy Water, Hashish and Jihad

LA Times
By Sebastian Rotella, Times Staff Writer
23 February 2004
The Muslim extremists responsible for the Madrid train bombings financed the plot by selling drugs, investigators say.

The hashish came from Morocco. The ideologues of the terror cell justified selling drugs as a weapon of jihad. The Moroccan dealer who financed the plot traded a load of hashish for the dynamite that slaughtered 191 people aboard commuter trains on March 11. The drug trafficker led the cell along with a Tunisian economics student, a duo whose disparity reflects the evolving nature of Islamic terrorism. Both blew themselves up after a standoff with police last month.