Minnesota cold-case suspect alleges constitutional violations in DNA database search

Private services intended for individuals to conduct genealogical research have increasingly been used by police and researchers to crack long-unsolved crimes, but the tactics present legal issues that have never before been litigated in Minnesota.

Michael Carbo Jr.

VIRGINIA, Minn. — The Chisholm Police Department's hiring of a private company to comb DNA databases in search of the perpetrator in a decades-old killing was illegal, and all evidence obtained as a result should be tossed, a defense attorney argued.

Public defender J.D. Schmid said law enforcement, in cooperation with Parabon NanoLabs, searched two databases without warrant or consent from people whose genetic information was disclosed, in violation of Minnesota law and the state and federal constitutions.

Schmid represents Michael Allan Carbo Jr., 53, who made his first in-person court appearance Wednesday, June 30. nearly a year after he was first charged with the 1986 rape and killing of 38-year-old Nancy Daugherty.

The Minnesota Bureau of Criminal Apprehension said the case was the first in the state to be solved through the services of Parabon, a private company based in the state of Virginia.


Nancy Daugherty

Parabon, according to court documents, was provided a sample of the suspect's DNA from the crime scene and used genetic phenotyping — the identification of potential physical characteristics of the individual — as well as genetic genealogy, which involves identifying potential relatives and building family trees through commercially available genetic databases.

Parabon found several potential matches in databases and developed extensive family trees based on the DNA sample, developing what the company called a "hypothesis" that Carbo was the source. Chisholm police and the Minnesota Bureau of Criminal Apprehension then began pursuing him as a suspect, obtaining DNA samples from Carbo's garbage and later from him directly.

PREVIOUSLY: Arrest made in 1986 Chisholm homicide

But the use of Parabon has presented a series of constitutional and privacy issues that have never before been litigated in a Minnesota courtroom. While prosecutors have maintained that the company merely provided a "lead" for investigators to follow, the defense has argued that employees were engaged in law enforcement work.

Schmid, in a written motion ahead of Wednesday's hearing, asked Judge Robert Friday to suppress "evidence of all comparisons of (Carbo's) DNA with the DNA profiles obtained from evidentiary samples in this case." Parabon, according to court documents, searched two databases known as FamilyTreeDNA and GEDMatch, which both allow users to submit personal DNA samples for genealogical purposes.

"The persons who have their DNA in databases maintained by FTDNA and GEDMatch did not authorize the disclosure of their genetic information in a manner than complies with Minnesota law," Schmid wrote.

The defense attorney also suggested that the warrantless seizure of Carbo's garbage was a violation of state and federal constitutions, and that forensic testing of the garbage and a direct sample from Carbo "constitutes the fruits of earlier unlawful searches of the DNA databases."


Schmid did not call any witnesses at Wednesday's contested hearing, agreeing to work with St. Louis County prosecutor Chris Florey to submit a written factual basis to the court, after which both attorneys will file briefs explaining their positions.

Judge Friday suggested the attorneys address a number of legal issues, including any privacy rights maintained by customers who use the private genetic databases, as well as the appropriate remedies for any constitutional violations in the course of a criminal investigation.

Controversial tactic

Law enforcement use of genealogical databases is an emerging, yet controversial, tactic for solving decades-old homicides. Notably, Joseph James DeAngelo, the "Golden State Killer," who committed at least 13 murders and more than 50 rapes in California between 1973 and 1986, was identified and arrested in 2018 based on DNA samples provided by distant relatives for genealogical purposes and maintained by GEDMatch.

The tactics have also been showcased in the popular true-crime genre. Parabon's head genetic genealogist, CeCe Moore, who directly worked on Carbo's case, appears on an ABC television show "The Genetic Detective," in which she recounts past cold cases she has helped solve.

Schmid also renewed a motion to gain access to additional information maintained by Parabon, including standard operating procedures, case notes, communications, documentation of database searches, and personal details and family trees of other people identified as potential matches for the DNA.

PREVIOUSLY: Defendant in 1986 Chisholm killing not entitled to DNA database details, judge rules

Friday denied a defense motion in May alleging a violation of discovery rules, finding that the defense had not proven the information to be relevant, as Parabon merely provided "general information" that drove law enforcement to conduct its own investigation into Carbo. The company also has maintained that the withheld information is proprietary.

Schmid, in the motion filed this week, said a long series of emails, obtained through a subpoena, show that Chisholm Police Chief Vern Manner was engaged in routine communication with Parabon officials between November 2019 and July 2020.


"Parabon acted entirely at the direction of the state and its sole function in this case was to assist with law enforcement's investigation into (Daugherty's) death," Schmid wrote. "Complete discovery from Parabon is necessary to ensure compliance with the discovery rules and due process."

Florey asked the judge to again deny the motion.

"All it does is corroborate the court's previous findings of fact," the prosecutor said Wednesday. "The state's position is that this is not a surprise; it's not new information."

Friday indicated he is likely to rule on both issues in September. Carbo, facing a count of intentional second-degree murder, remains in the St. Louis County Jail on $1 million bail.

Tom Olsen has covered crime and courts for the Duluth News Tribune since 2013. He is a graduate of the University of Minnesota Duluth and a lifelong resident of the city. Readers can contact Olsen at 218-723-5333 or
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