PHOENIX — Citing 17th century English law, the state Court of Appeals concluded Thursday that someone charged with shoplifting is entitled to demand a trial by jury.

In a unanimous decision, the judges said the Arizona Constitution makes it clear that if a jury trial was mandated for a crime during territorial days, that right remains more than a century later.

They said the fact that the crime is only a misdemeanor, punishable by six months in jail, does not override a constitutional right.

Thursday’s ruling is most immediately a defeat for the city of Peoria, which had argued against having to go through the time and expense of a jury trial. But the decision has implications for other city and county prosecutors who have, until now, convinced municipal judges and justices of the peace that they have judicial authority decide a shoplifter’s guilt.

Both the state and federal constitutions entitle people charged with crimes to a trial by jury. But courts generally have held that right does not extend to offenses that can result in jail time of less than six months. And that means all misdemeanors.

But the state constitution, adopted when Arizona became a state, says, “The right of trial by jury shall remain inviolate.”

Appellate Judge Lawrence Winthrop, writing Thursday’s ruling, said that means if someone were entitled to a jury trial prior to 1912 for a comparable common-law offense, then that right continues to exist.

In an effort to undermine that logic, attorneys for Peoria argued shoplifting was not a common-law offense — essentially one that was always considered a crime just based on custom — but actually based on a 17th century enactment of the English Parliament, dubbed “An Act for better apprehending prosecuting and punishing of Felons that commit Burglary Housebreaking or Robbery in Shops Ware-houses Coach-house or Stables or that steal Horses.”

Winthrop said that citation ignores other evidence.

“Both before and after enactment of the 1698 statute, defendants in 17th century London were accused of shoplifting and afforded a trial by jury at Old Bailey Courthouse, London’s criminal court,” the judge wrote.

And to prove his point, he even quoted from court records.

In one case, Anne Jenkins and Elizabeth Green were accused of stealing 18 yards of muslin, valued at 52 shillings, which belonged to William Peat. The record shows both denied the theft but, after testimony by a witness, “were found guilty of Felony.”

This isn’t the first time that appellate courts have upheld the right to a jury trial for minor offenses.

Winthrop pointed out that it isn’t simply a question of whether there was a right to a trial by jury prior to 1912. He said even those charged with other misdemeanors can demand jury trials if an offense is considered serious.

In 2008, for example, the state Supreme Court decided that Monsignor Dale Fushek was entitled to have a jury decide whether he molested teens while he was the pastor of St. Timothy Catholic Community in Mesa.

The justices said that’s because state law would allow a trial judge to order Fushek to register as a sex offender if convicted. And that, the high court concluded, shows the Legislature believes the offenses, while misdemeanors, are “serious crimes.”

Courts have also extended jury trials to those charged with resisting arrest. And there has been a general rule that crimes of moral turpitude, like prostitution, also entitle someone to a jury trial.

But a bid by some strippers for a jury trial for violating a Scottsdale ordinance was rejected.

In that case, the appellate court acknowledged there was a pre-statehood offense of indecent exposure, a law that did entitle those charged with violating it to a jury trial. But the judges said the Scottsdale ordinance simply regulates nude dancing and does not prohibit it outright.

More recently, state lawmakers voted in 2012 to spell out in statute that those facing first-time misdemeanor charges of driving under the influence of alcohol are entitled to a jury trial. That legislation overturned a 2011 court ruling to the contrary.