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Adam Mersereau

Other Wyoming Exonerations
Seal of Converse County,  Wyoming
In the fall of 2009, Danielle Mersereau, of Glenrock, Wyoming, watched a television program about sexual abuse of children by stepparents. She then researched the subject on the Internet, and asked her 4-year-old son, L.W., whether his stepfather, 23-year-old Adam Mersereau, had ever anally penetrated him or touched his penis inappropriately. L.W. answered no. However, at breakfast one morning in December, L.W., unsolicited, said Adam anally penetrated him. Both parents were alarmed and decided to limit L.W.’s exposure to inappropriate media.

About six months later, in May 2010, L.W. told his mother that he had exposed himself to another boy at school. On May 13, Danielle took L.W. to see a physician’s assistant where Danielle related the December and May incidents in front of L.W.

On May 25, Danielle, in L.W.’s presence, made three phone calls--two to her sister and one to her sister-in-law--during which she described the December incident using the terms “peepee” and “butthole.” That same day, Danielle took L.W. to see a doctor who referred them to the Department of Family Services.

The following day, Nicole Rosenberger of the Child Advocacy Project conducted a forensic interview with L.W. The Child Advocacy Project is a nonprofit agency that assists law enforcement investigations of mistreatment of children. Rosenberger used anatomical dolls in questioning L.W., who denied that anyone had sexually assaulted or molested him for the first 20 minutes of the interview. Rosenberger then told L.W. his mother had related that his “dad put his peepee in your butthole.” Over the next 40 minutes, Rosenberger asked leading questions and used the phrase “daddy stuck his peepee in [your] butthole” approximately 35 times. Eventually, L.W. stated that Adam had sexually assaulted him on May 21 while they were at a park where Adam went to drive the car through the mud for sport.

Officer Ben Peech, of the Converse County Sheriff’s Department, observed the interview. He immediately brought Adam in for questioning and interviewed him for four hours. During the interview, Peech described himself as “an instrument of God.” Adam reported being exhausted during this interview, and he eventually admitted touching L.W.’s penis and anus for 30 seconds or less while washing him. He stated that the touching was inappropriate, but that it was not done for sexual gratification and he denied sexually penetrating L.W. Peech arrested Adam at the conclusion of the interview.

Traci Jones, a sexual assault nurse examiner, conducted a videotaped physical examination of L.W. on May 27. She observed a wedge-shaped scar, which she reported as evidence of anal tearing. She also reported that when L.W. voluntarily pulled his cheeks apart, his anus dilated immediately. This dilation, she stated, was very unusual, having observed it only twice in around 300 examinations.

On June 1, Adam was charged with first-degree sexual abuse of a minor for the May 21 incident, and second-degree sexual abuse of a minor for the bathing incident.

Prior to trial, Adam’s attorney, Hampton M. Young, Jr., was unable to find a physician to review Jones’s report, but sexual assault nurse examiner, Judy Malmgren, agreed to testify for the defense.

The trial began on December 6, 2010 in Converse County District Court. A DNA analyst, Kathryn Normington, testified for the prosecution that she found stains that may have been blood on L.W.’s pajamas. These stains tested negative for sperm, but one stain contained the DNA of more than one person. Normington testified that neither Adam nor L.W. could be excluded as possible contributors to the mixture.

Jones testified about the wedge-shaped scar, and stated that the anal dilation she observed indicated blunt force trauma. However, on cross-examination, Jones admitted that anal dilation is inconclusive for sexual assault. Jones also testified that it would be difficult for someone who just viewed the videotape to see exactly what Jones saw during the examination.

The prosecution also introduced, over objection, more than a dozen nude photographs of L.W. and his two-year-old brother E.M. that were found on the family computer, among hundreds of other non-nude family photographs. All but two of the photos were taken by Danielle. The photos showed the children playing in the mud, sitting on Adam’s lap in the bath, and one showed a child face down on the bed with his buttocks in the air. The prosecution contended that these photographs were evidence of an anal fetish, but the defense characterized them as ordinary family photographs.

A computer expert from the Wyoming Division of Criminal Investigation testified for the prosecution that Adam’s computer had accessed child pornography websites. Immediately before this testimony, the court gave a limiting instruction to the jury that included the following statement: “I believe you are about to hear evidence that there were child pornography websites on the defendant's computer.” However, the computer expert never established that the websites contained child pornography. Instead, he admitted that state policy prevented him from actually visiting or viewing any of the allegedly pornographic websites to verify what they contained.

The defense moved to have L.W. declared incompetent to testify. McCoy Dean Haddock, a clinical psychologist who was seeing L.W., testified that L.W. had a vivid imagination and that his memory was easily contaminated. Haddock and another defense witness, forensic psychologist Chuck Denison, also testified that Rosenberger’s use of anatomical dolls during her interview with L.W. was inappropriate.

After a competency hearing, the court ruled that L.W. could testify. At one point, L.W. testified that “Daddy told me not to tell.” He had not made this statement in any earlier interviews.

Malmgren, a sexual assault nurse examiner, testified for the defense that the wedge-shaped scar was the result of diastasis ani, a congenital condition, and that there was no evidence of sexual assault. She also testified that anal dilation is inconclusive for sexual abuse.

A computer expert testified for the defense that some of the websites cited by the prosecution were not listed as child pornographic websites on a list maintained by the National Center for Missing and Exploited Children. The defense expert also questioned whether one of the websites had even been accessed at all. Perhaps most significantly, the expert noted that the prosecution’s expert could not establish that Adam, as opposed to any other user, had visited the web sites. Indeed, circumstantial evidence suggested that Danielle, who had admitted at a pre-trial hearing that she viewed adult pornography on that computer, was more likely the user.

On December 10, 2010, the jury found Adam guilty on all counts.

After the trial, Malmgren referred Young to Dr. Joyce Adams. Dr. Adams was a professor of clinical pediatrics at the University of California, San Diego School of Medicine and board certified in child abuse pediatrics. On January 7, 2011, Adams signed an affidavit stating that she had viewed the videotaped physical examination, and there were “absolutely no signs of” anal injury. The anal dilation reported by Jones was minor, not complete, and common in children who both had and had not been sexually abused. Adams also agreed with Malmgren’s opinion that the scar was diastasis ani. Finally, she stated that the videotape was of good quality and permitted a thorough evaluation of L.W.’s anatomy. She stated that it was “inaccurate and misleading” of Jones to claim that the quality of the videotape made any peer review of the examination difficult.

On January 10, 2011, Young submitted a motion for judgment of acquittal or for new trial. In addition to Dr. Adams’s affidavit, the motion included an affidavit from Joy Mersereau, L.W.’s grandmother. Joy, who had not attended the trial, later learned of L.W.’s testimony that “Daddy told me not to tell.” Joy said that she “instantly recognized” the comment as a reference to a conversation she had with L.W. in December 2009 about Adam’s concern that Danielle would be upset for getting her car muddy the day they were at the park. Affidavits by Haddock and by Adam himself corroborated this explanation of the “Daddy told me not to tell” remark. The motion was denied without a hearing, and on May 6, 2011, the judge sentenced Adam to 18 to 24 years in prison.

On September 26, 2012, the Supreme Court of Wyoming reversed Adam’s convictions. The court found that the trial judge erred in finding L.W. competent to testify, and in admitting the nude photographs and computer evidence. The court further found that the judge’s limiting instruction improperly commented on the weight of evidence and mischaracterized the computer expert’s testimony. Finally, the court found the evidence insufficient to support the conviction for the bathing incident. The court dismissed that charge and ordered a new trial on the other charge.

On October 12, 2012, the prosecution dismissed the remaining charge.

– Simon Cole

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Posting Date: 5/27/2017
Most Serious Crime:Child Sex Abuse
Additional Convictions:
Reported Crime Date:2010
Sentence:18 to 24 years
Age at the date of reported crime:23
Contributing Factors:False Confession, False or Misleading Forensic Evidence, Perjury or False Accusation, Official Misconduct
Did DNA evidence contribute to the exoneration?:No