Tuesday, July 12, 2016

Field Drug Tests, Racial Disparities, Wrongful Convictions, and How Houston Cleaned Up Its Mess

This week, the New York Times Magazine published an article on the exonerations of dozens of people who had pleaded guilty to drug felonies in Harris County, despite the fact that the substances they possessed were not controlled substances. People were wrongly arrested on account of notoriously unreliable drug field tests that HPD (and many departments around the country) used.

According to the article, Las Vegas authorities "reexamined a sampling of cocaine field tests conducted between 2010 and 2013 and found that 33 percent of them were false positives." Drug field tests are so unreliable that "[b]y 1978, the Department of Justice had determined that field tests 'should not be used for evidential purposes,' and the field tests in use today remain inadmissible at trial in nearly every jurisdiction; instead, prosecutors must present a secondary lab test using more reliable methods."

The problem is that people--even innocent people--who are stuck in jail because they are too poor to post bail--so desperately want to get out of jail that they plead guilty quickly, before the secondary lab tests can be completed. The article notes that Harris County public records show that "99.5 percent of drug-possession convictions are the result of a guilty plea," and a majority of those are felonies.

The article points to Hurricane Katrina in 2005 as the point in time when HPD began pushing field tests to make more drug arrests to counter a feared increase in crime by the refugees from Louisiana. The reporters examined the Harris County case files and found "stark" racial disparities: "Blacks made up 59 percent of those wrongfully convicted in a city where they are 24 percent of the population, reflecting a similar racial disparity in drug enforcement nationally."

The injustices came to light due to the diligent work of James Miller, Manager of the Controlled Substances Division of the Houston lab who makes sure all drug evidence is tested, even in cases where defendants have long since pleaded guilty. Credit also goes to Inger Chandler, the chief of the District Attorney's Conviction Integrity Unit, who followed up on a tip about possible wrongful convictions and tracked down all the lab reports indicating "No Controlled Substance" that Miller had been sending the DA's office for years.

The Houston lab got other good publicity, this time about its quality control. A report by the National Forensic Science Commission recently endorsed the use of "blind" testing as an important innovation in quality control in forensic science and recognized the Houston Forensic Science Center (at fn. 18) as one of only two forensic labs in the world that have implemented it. The other lab is in The Netherlands.

After the debacle of the Houston Police Department Crime Laboratory, the City of Houston in 2014 spun off the crime lab, making it a new organization, independent of law enforcement, now called the Houston Forensic Science Center. Today the lab also has no backlogs in major sections like controlled substances, DNA, and firearms, among others, as reported at the July monthly meeting of the lab's Board of Directors.

The Houston lab also announced this week that it is hosting a symposium called “Exonerations and Backlogs” on August 11th at St. Thomas University. Speakers will include Debbie Smith, a rape victim who is now the CEO of H-E-A-R-T, Inc., a non-profit foundation established to aid victims of sexual assault, as well as Anthony Graves, an exoneree who was released from death row after over 15 years and the founder of a non-profit foundation designed to promote fairness in the criminal justice system. CLE credit is pending.


Alex Bunin said...

And credit goes to Nicolas Hughes of the Harris County Public Defender's Office who spent thousands of hours tracking down the wrongly convicted, getting their permission to act on their behalf, and filing writs for them. The article left that out, even though the authors had plenty of information about his role.

Lee said...

Do those wrongfully convicted get their convictions and arrests automatically expunged and compensation as directed by the legislature? Or do they have to hire lawyers out of their own pocket to clean up all this mess made by the police and prosecutors without so much as an apology?

Anonymous said...

So, the manufacturer of the botched tests -- Lynn Peavey Company, the Safariland Group and Sirchie -- are going to compensate the States and the defendants for their crappy product? And these groups are taking steps identify the "false positives" to change their product to give more accurate results? And Police Agencies are switching to more reliable presumptive tests?

Or is everyone satisfied with just shrugging their shoulders and collecting a paycheck?

Who is going to held accountable for such a systemic screw-up?

(Image whose head would roll if a pharmaceutical sold a product that incapacitated people 33% of the time is was used? What other profession allows for a 33% failure rate?)

Bill Habern said...

Alex Bunin is correct to point out the efforts of Nick Hughes of the HCPD appellate division and these efforts. This is not the last time you will be hearing about the exceptional talent of this young lawyer. He has also contributed substantial efforts to challenging the absurd civil commitment issues in Texas.

Bill Habern

Soronel Haetir said...


Baseball tolerates far higher failure rates. There a .666 failure rate is doing very good.

And I was reading about getting the Oak Ridge plant operational during WW2 the other day, there was a sieve being made out of nickel, it was when they got the _success_ rate at making these as high as 45% that they went ahead with that particular process.

Anonymous said...

Those drug testing kits were taught all across the country as being much more reliable than current figures indicate. Blaming the courts or the cops as though they should have known better is unreasonable, the big bucks manufacturers sparing no effort in providing free samples and training for years.

Anonymous said...


Field drug tests are screening tests only, and investigative tools only. They should always be followed up by confirmatory laboratory tests. The police use positive test results as a way to induce confessions. I don't expect the police to know any better. I certainly don't expect the suspects to know any better. But the attorneys who prosecute and defend these cases certainly should know better.

Anonymous said...

09:09 -

You appear to be unfamiliar with the basics of analytical tests. There is good information on the web, much of it directed at non-scientists. You might want to take a look at it. Look up "confusion matrix". That will lead you in the right direction.

Bottom line: All screening tests have false positive and false negative error rates. That these error rates exist is expected. For comparison, the single-test false positive error rate for mammography in detecting breast cancer is on the order of 15%. For a woman having annual mammography, there is about a 50% chance she will have at least one false positive result over a ten year time period.

Anonymous said...

@2:50- "Bottom line: All screening tests have false positive and false negative error rates. That these error rates exist is expected."

Didn't read the article, did ya?

The problem arises when the stated error rates of the manufacturers are much, much worse than the true error rates. Or, as stated in the hyperlinked article "There are no established error rates for the field tests, in part because their accuracy varies so widely depending on who is using them and how."

Perhaps you can help the authors of the NYT Magazine with your wunderkind insight.

If the field tests have such largely uncontrolled influential variables, why are they being used at all. Why are they called "tests"?

Flipping a coin is a test. Could we just use that to determine if an unknown sample is or is not methamphetamine? (This is a rhetorical question anonymous 2:50. You don't have to answer it, really.)

And did you want to complete your mammography comparison examples with the 101+ variables that influebce those uncited statistics, or did you pull those numbers from your "confusion matrix"?

Anonymous said...

Anon 7/13/2016 01:41:00 PM, yes but the results are confirmed after the suspect is placed under arrest, the lowly patrol officer having to follow whatever established procedures and policies his agency demands. If that takes one day or six months, it is not under the control over the officer making the arrest. That suspects carrying such substances know they are carrying them and know they will get the best deal by pleading guilty is a given, just ask a sample of them.

Anonymous said...

You said: "The main weaknesses in the study revolve around its limited data collection and overly broad interpretation, and its failure to take into account how racial biases impact policing and police reporting." Have you already decided racism is the causal factor?
So what additional independent variables are needed and what to you propose as a valid and reliable measure of 'racial biases'. Will the variable for bias be for both all actors or just police?
The regressions speak for themselves, and to me raise more questions, in both the analysis and conclusions.