Sometimes mysteries arise from the quiet cubicles of the Maricopa County Assessor's Office, giving real-estate analysts a chance to practice Sherlock Holmes-like sleuthing.
One recent case involved figuring out why a Chandler property repeatedly went to tax-lien auctions and racked up $90,000 in unpaid taxes over three decades.
The problem they discovered: The property didn't belong to a person.
Instead, the three-lane slab of asphalt and a median on the west side of Price Road has belonged to the city of Chandler for years. But the parcel and street didn't look that way on the books.
It's the weirdest example staffers can recall of a phenomenon known as "orphan" parcels — tracts of land that, like zombies, live on the property-tax rolls even though they should have been eliminated long ago.
There are costs attached — sometimes for adjacent landowners who unwittingly pay the property tax bill for these orphans, sometimes for tax-lien investors who learn the parcels whose tax debt they've purchased cannot, in fact, be foreclosed. Ultimately, there may also be a cost to government if it has to refund property taxes collected improperly on an orphan parcel.
The problem crops up through paperwork errors often made years earlier, said Assessor Paul Petersen.
"The one you're talking about is the most egregious one I've heard about in my tenure as assessor," said Petersen, who has worked in the office for more than a decade. "They might be kind of funny to talk about, but they occur because people change their properties for a million reasons."
The trickiest "orphan" parcels occur when the government buys or condemns land for roads, bridges or other projects. Officials are supposed to file a new designation to record the land as public property not subject to taxation.
But when that document falls through the cracks, county officials continue to send tax bills for the land. Sometimes they bounce back unpaid, or they find their way to a private owner who pays the taxes unknowingly.
That's what happened on that strip of Chandler pavement back in 1987.
When the city wanted to widen the street, it condemned a slice of farmland that borders Price Road today. But for some reason too old to research, the new designation of the thoroughfare didn't show up on the assessor's books.
One owner paid some taxes on it. Then the property's tax liens were sold at auction. Finally in 2015, an investor who purchased the liens alerted the County Treasurer's Office to the error. The Assessor's Office issued a correction and the county abated some of the taxes.
Messages left with former lien-holders to discuss the problem went unanswered, However, Assessor's Office staffer Ryan Smith joked that "all is right with the world" now.
Given the 1.7 million parcels that Maricopa County keeps track of, Petersen said, these mysteries don't occur very often — maybe a few times a year.
And though the discoveries sometimes end in tax refunds, they don't add up to much, Petersen said, since most of the money paid back originally came from the tax-lien investors.
"When we're as big as we are, with as many parcels as we have, with as few staff as we have, we run one of the most efficient assessor's offices in the country," Petersen said. "It might sound boring, but one of our jobs is to make sure the citizens of Maricopa County have trust in the government and their property taxes. ... We've made a concerted effort to make the (property) roll more accurate."
County officials have had more time to search for "orphan" parcels since the Great Recession of 2008 slowed down the real-estate business.
The effort has paid off, according to Petersen.
"I hear about them less and less," he said.
If you have questions about your property-tax bill, call the Maricopa County Assessor's Office at 602-506-3406. The office is open Monday through Friday from 8 a.m. to 5 p.m.