A court order compelling a suspect to provide a fingerprint to unlock a cellphone doesn't violate their constitutional rights, the Minnesota Court of Appeals ruled Tuesday.

Although the court has allowed police to obtain blood, fingerprint or handwriting samples even against the defendant's wishes, this is the first time the appeals court has ruled on fingerprints to gain access to a cellphone.

In a 17-page ruling, Judge Tracy Smith wrote that ordering the fingerprint doesn't violate a person's privilege against self-incrimination. She also argued that being ordered to produce a fingerprint isn't the same as being forced to testify against yourself in court.

Peter Ivy, Carver County's chief deputy attorney, said he wasn't surprised by the ruling because the state already allows court orders to compel samples of everything from hair to urine. In the past, the county's computer forensic experts could just download a cellphone's information if no security measure like a fingerprint was in place, he said.

"Cellphones are ubiquitous," he said. "Prosecutors have to do their due diligence to look at different avenues to collect evidence."

The ruling follows a 2014 burglary case involving Matthew V. Diamond. who was charged with stealing a safe, laptop and jewelry from a home in Chaska. He was arrested several months after the burglary on an unrelated outstanding warrant.

While Diamond was jailed, a Chaska police detective visited him and noticed a similarity between the tread of his shoes and the shoe prints left by the garage at the house burglarized. The detective obtained a warrant for his shoes and cellphone, but wasn't able to unlock it.

"Back in 2014, it was the first time I had ever come across a phone that needed a fingerprint to unlock it," said Chaska Police Lt. Rachel Nelson. "A lot has changed since then."

That's why a motion was filed in Carver County District Court to compel Diamond to provide his fingerprint. A judge signed the warrant, saying it wouldn't violate his constitutional rights.

Diamond was found in civil contempt for refusing to give his fingerprint, but later complied and his cellphone was immediately searched.

At trial, a witness testified that Diamond used her car on the day of the burglary and that he gave her stolen jewelry, which they pawned in Shakopee. The prosecution also introduced evidence of his cellphone use in the area of the burglary and shoe prints.

Police were able obtain incriminating evidence once the cellphone was unlocked, according to the ruling.

He was convicted of burglary and several other crimes, and was sentenced to nearly six years in prison.

In his appeal, Diamond argued that the Fifth Amendment provides that no person "shall be compelled in any criminal case to be a witness against himself." Unlike blood or saliva, giving a fingerprint to unlock the cellphone relates a factual assertion or discloses information.

Shawn Webb, who supervises serious felony cases for Hennepin County's public defender's office, said the ruling is a troubling expansion of the things a defendant can be compelled to provide. He cited a federal court of appeals case that ruled the Fifth Amendment would be violated if a person was compelled to provide their password or code to unlock a computer.

"And the ruling doesn't even address if the defendant is protected against self-incrimination once the evidence is reviewed from the cellphone," he said.

The American Civil Liberties Union of Minnesota didn't comment Tuesday because they hadn't read the ruling. Nelson said she has no doubt the ruling will be very helpful to law enforcement.

Ivy agreed. "Who knows what the future holds?" he said.

David Chanen • 612-673-4465