New York Times

By RAYMOND BONNER

WASHINGTON, July 22 — Mario Marquez did not deny rap­ing and mur­der­ing his 18-year-old wife and her 14-year-old niece, the crimes for which he was con­vict­ed in 1984 and exe­cut­ed 11 years later.

But on appeal, Mr. Marquez’s lawyers pre­sent­ed evi­dence that he was men­tal­ly retard­ed and suf­fered from severe brain dam­age, the result of beat­ings by his father, with sticks, whips and clubs. When he was 25, Mr. Marquez had dif­fi­cul­ty count­ing mon­ey and thought the five largest cities in the United States were Montana, Oregon, Wisconsin, New York and New Orleans, accord­ing to a test giv­en to him by a state-appointed psychologist.

The State of Texas did not dis­pute any of this. A Texas dis­trict court, in rul­ing on one of Mr. Marquez’s appeals, found that he was a dam­aged child func­tion­ing in an adult life” and that he was mild­ly men­tal­ly retard­ed,” with an intel­li­gence quo­tient of 65 to 70, com­pared with a nor­mal I.Q. of about 100.

Mr. Marquez was one of six retard­ed inmates exe­cut­ed since 1990 by

Texas, accord­ing to the Death Penalty Information Center, a non­prof­it orga­ni­za­tion in Washington. Alabama, Florida, Louisiana and Virginia each exe­cut­ed four retard­ed inmates and South Carolina exe­cut­ed three, accord­ing to the cen­ter. In all, the cen­ter lists 35 such cas­es in 12 states.

The debate about whether any men­tal­ly retard­ed per­son should be exe­cut­ed has inten­si­fied recent­ly, as state gov­ern­ments and the Supreme Court are address­ing the issue.

In June, Gov. Rick Perry of Texas went against the trend in oth­er states when he vetoed a bill that would have barred the exe­cu­tion of the men­tal­ly retard­ed. Mr. Perry denied that Texas had exe­cut­ed any­one who was mentally retarded.

This month, when he signed leg­is­la­tion that pro­hibits the exe­cu­tion of the men­tal­ly retard­ed, Gov. Bob Holden of Missouri said, I real­ize this is now a nation­al issue since the gov­er­nor of Texas refused to sign a sim­i­lar bill, but I believe this is the right thing to do.” Two weeks lat­er, Connecticut
enact­ed a similar law.

Of the 38 states with the death penal­ty, 17 pro­hib­it the exe­cu­tion of the men­tal­ly retard­ed, as do the fed­er­al gov­ern­ment and the District of Columbia.

In the fall, the Supreme Court will hear argu­ments from the lawyers who say that exe­cut­ing some­one who is men­tal­ly retard­ed is cru­el and unusu­al pun­ish­ment, in vio­la­tion of the Eighth Amendment. The death row inmate in the case is Ernest P. McCarver, who was con­vict­ed in North Carolina for the mur­der of a fel­low cafe­te­ria work­er. Mr. McCarver has an I.Q. of 67. In gen­er­al terms, peo­ple are con­sid­ered men­tal­ly retard­ed if they have I.Q.‘s below 70, have dif­fi­cul­ty per­form­ing every­day tasks and have shown signs of the con­di­tion before age 18.

In 1989, when only two states barred the exe­cu­tion of the retard­ed, the Supreme Court ruled, in the case of Johnny Paul Penry, a Texas death row inmate whose I.Q. is 51 to 63, that the Eighth Amendment does not pro­scribe exe­cu­tion of the men­tal­ly retard­ed. But the court said pro­ce­dur­al flaws in Mr. Penry’s case pre­clud­ed his exe­cu­tion, and this year, after he was sen­tenced to death again, the court again spared him, rul­ing that the jury had not been prop­er­ly instruct­ed on how to con­sid­er the evi­dence of Mr. Penry’s retar­da­tion when decid­ing on the sentence.

One month after the 1989 deci­sion in the Penry case, Alabama exe­cut­ed Horace Dunkins, who had been con­vict­ed of rap­ing and mur­der­ing a 26-year-old moth­er of four. Mr. Dunkins had an I.Q. of 69 and the rea­son­ing skills of a 12-year-old, but this evi­dence was nev­er pre­sent­ed to a jury.
After one juror learned of it lat­er, she signed an affi­davit say­ing she nev­er would have vot­ed for the death penal­ty had she known of Mr. Dunkins’s mental retardation.

The first state to pass a law to pro­tect the men­tal­ly retard­ed was Georgia, large­ly because of a pub­lic out­cry fol­low­ing the exe­cu­tion in 1988 of Jerome Bowden, who was con­vict­ed of rob­bing and killing a 55-year old woman and severe­ly beat­ing her moth­er. Mr. Bowden’s school records showed he had an I.Q. of 59. As an adult he could not count to 10, and he worked mop­ping floors at Goodwill Industries, in a pro­gram for the mentally retarded.

At tri­al, Mr. Bowden’s lawyers pre­sent­ed none of the evi­dence of his men­tal retar­da­tion to the jury. When his appel­late lawyers, who found the school records and oth­er evi­dence of retar­da­tion, tried to raise the issue in fed­er­al court, they were barred from doing so, because the issue had not been
raised dur­ing the trial.

In reject­ing Mr. Bowden’s appeal for clemen­cy, the Georgia Board of Pardons and Paroles said he knew right from wrong.” That is often the stan­dard that offi­cials give when they assert that no men­tal­ly retard­ed per­son has been exe­cut­ed in their states. Governor Perry of Texas said the six inmates exe­cut­ed in his state who experts say were men­tal­ly retard­ed were not because they knew what they were doing was wrong.”

But this is con­fus­ing two tests of a defen­dan­t’s men­tal state. Whether a defen­dant knows right from wrong is the test for crim­i­nal insan­i­ty — a defen­dant who does not know right from wrong may be found not guilty by rea­son of insan­i­ty. Most men­tal­ly retard­ed peo­ple are not insane, and they know right from wrong. In states that pro­hib­it the exe­cu­tion of the men­tal­ly retard­ed, the ques­tion of whether a per­son is men­tal­ly retard­ed is raised in the sen­tenc­ing phase of the tri­al, after the defen­dant has been found guilty.

Although there is no ques­tion of his san­i­ty, Mr. Bowden’s appel­late lawyers say there is a good chance he was innocent.

An accom­plice received a life sen­tence in exchange for tes­ti­fy­ing against Mr. Bowden. Initially, Mr. Bowden denied hav­ing killed the woman, say­ing his friend had done it. But then the police brought a doc­u­ment to him in his cell. He could not read it. But he signed it. It was a confession.

Confessions by a per­son who is men­tal­ly retard­ed are high­ly prob­lem­at­ic, men­tal health experts say, because retard­ed peo­ple often are sus­cep­ti­ble to sug­ges­tion and eager to please the authorities.

You can talk them into things,” said Timothy Derning, a psy­chol­o­gist who has been an expert wit­ness in cap­i­tal cas­es around the coun­try. They may know right from wrong, but they don’t trust their own opin­ions. For this rea­son, they often confess.”

The exe­cu­tion of Mr. Bowden, in 1988, was such a hideous occur­rence that it shamed the Legislature into pass­ing the retar­da­tion law,” said August Siemon, an Atlanta lawyer who rep­re­sent­ed Mr. Bowden in his appeals. But it is not a very sat­is­fac­to­ry law from the view of defen­dants who are men­tal­ly retard­ed, Mr. Siemon said, because it requires them to prove their retar­da­tion beyond a reasonable doubt.

Most of the states that have laws ban­ning the exe­cu­tion of the men­tal­ly retard­ed, includ­ing New York, only require defen­dants to prove their con­di­tion by a pre­pon­der­ance of the evidence.”

The law in Arizona, which the gov­er­nor signed in April, requires the court to appoint a psy­chol­o­gist to exam­ine a defen­dant in a cap­i­tal case, and if the defen­dan­t’s I.Q. is below 75, then fur­ther test­ing by psy­chol­o­gists is required. Ultimately, the judge, not the jury, decides if a defen­dant is mentally retarded.

In 1996, Arizona exe­cut­ed Luis Mata, who was con­vict­ed of rape and mur­der. He had been born with water on the brain, and he frac­tured his skull when he was 6. He had an I.Q. of between 65 and 70, and as an adult he could only count on his fin­gers. None of this evi­dence was pre­sent­ed to the
jury, and years lat­er, when the pros­e­cu­tor learned of it, he said he was shocked and upset.”

In an affi­davit, the pros­e­cu­tor, Michael Donovan, said that had he been aware of the evi­dence of Mr. Mata’s men­tal retar­da­tion, I would not have request­ed or pur­sued a death sentence.”