Despite his perfect prison record, Mr. Coble was resentenced to die at his 2008 sentencing trial, in large part because of the testimony of Dr. Richard Coons. Dr. Coons testified that Mr. Coble was likely to pose a "future danger," a required finding in Texas before the jury can impose death. The Texas Court of Criminal Appeals (CCA) found - for the first time ever - that the testimony of an "expert" on future dangerousness violated the rules of evidence because it was so utterly unreliable. As the CCA concluded, Dr. Coon's testimony was based on his own, idiosyncratic, subjective methodology. Dr. Coons was unable to cite to a single book, treatise or article discussing any of the factors he identified as important in his methodology.
Although the CCA found the testimony unreliable, it concluded that it was harmless error because it was only evidentiary, rather than constitutional error. The CCA erroneously interpreted a Supreme Court case, Barefoot v. Estelle, to mean that the constitution is never violated by the admission of expert testimony in sentencing, no matter how utterly unreliable that testimony is. Our brief asks the Supreme Court to correct the CCA's error and restore Mr. Coble's constitutional right to reliable sentencing in capital cases.