SEATTLE — Prosecutors in Washington state are re-examining their use of a little-known law that allows police to obtain bank, phone and other records without a search warrant, after an Associated Press story raised questions about the practice.

Tom McBride, executive secretary of the Washington Association of Prosecuting Attorneys, said Tuesday that investigators have drifted toward becoming too reliant on the “special inquiry judge proceedings,” and should only use them when traditional investigative techniques won’t suffice.

“This is not intended to be for mainstream, daily use,” McBride said. “We were deferring a little too much to law enforcement requests.”

McBride said he is drafting a list of best practices to help standardize the way prosecutors around the state handle special inquiries.

The proceedings were created by the Legislature in 1971 and designed largely as a way to compel testimony or obtain evidence in complex public-corruption or organized-crime investigations, but some jurisdictions have used them for run-of-the-mill matters, including drug and rape cases.

The special inquiries function as grand juries without the grand jury: At the request of a prosecutor, a judge can secretly hear from witnesses, review evidence or issue subpoenas based on a reasonable belief that someone “may be able” to provide testimony or evidence. The proceedings are used as investigators try to develop probable cause to charge someone with a crime.

To obtain a warrant to search someone’s home, person, car or records, police need probable cause, based on a sworn statement, to believe the thing being searched contains evidence of a crime. But under the special inquiry statute, they can obtain those same records with a subpoena secretly issued by a judge based on a lesser legal standard, reasonable suspicion. No sworn statements are required, though many jurisdictions say their investigators or prosecutors are under oath when they ask the judge for a subpoena.

Unlike a search warrant, there’s no public record of the special inquiries. If no charges are ever filed, the person targeted never learns that police obtained their records. Nor is there necessarily a “return” filed with the court, explaining what evidence was obtained. It’s not clear what becomes of the records seized.

Some defense lawyers call that “sneak-and-peek stuff.” They argue that the law violates open-government principles as well as the rights of the suspects under the state and federal constitutions.

“It’s a way to avoid complying with the warrant requirement. There’s no other way to describe it,” said Bob Thompson, a Pasco attorney who recently challenged the use of a special-inquiry proceeding in a defendant’s drug and weapons case.

The Fourth Amendment to the U.S. Constitution states that people have the right to be secure in their “persons, houses, papers, and effects, against unreasonable searches and seizures … and no Warrants shall issue, but upon probable cause, supported by Oath or affirmation.”

Washington’s Constitution is considered even more protective, requiring that people not be disturbed in their private affairs without “authority of law.”

No appeals court in the state has ever ruled on whether special inquiry subpoenas issued with less than probable cause constitute “authority of law.” McBride says it does. Thompson disagrees.

With the help of Seattle attorney Lenell Nussbaum, Thompson recently challenged the charges against Alfredo Ahumada Ozuna Jr. A detective involved in Ozuna’s case did obtain a search warrant for his house and car, but in a statement supporting the search warrant, the detective revealed that he had already reviewed Ozuna’s bank records.

There was no search warrant for the bank records. Nor had the lawyers been notified by the prosecutor’s office that their client was subject to a special inquiry subpoena.

Because charges were filed, they were able to obtain the transcript of the special inquiry proceeding, which revealed that no statements to the judge had been made under oath.

Their public records request to the Benton County Prosecutor’s Office turned up two thick binders’ worth of other cases in which detectives routinely asked prosecutors to get them secretly issued subpoenas for cellphone, email, mortgage and banking records in drug, fraud, identity theft, rape and other investigations.

The lawyers successfully petitioned to have Ozuna’s case transferred to Walla Walla County, so they could challenge the Benton County Superior Court’s practices regarding special inquiries, and they filed briefs arguing that the use of the special inquiry was unconstitutional.

Just when it appeared that Ozuna’s case was on track to be the first in Washington to reach an appeals court on that issue, it settled last week, with prosecutors dropping charges related to the special inquiry subpoena. Ozuna pleaded guilty to unrelated theft and drug-possession charges and was sentenced to time served.

Thompson and Nussbaum said they were pleased to get a good deal for their client, but disappointed to have to drop their challenge to the law itself.

“That’s the problem with challenging the system — sometimes it works best for your client to take another route,” Nussbaum wrote in an email. “It’s a victory for the client, but not yet a solution for the systemic problems.”

An AP story on Ozuna’s case in May found that prosecutors around the state use special inquiries to varying degrees. King County uses it about a dozen times a year, but Pierce County Prosecutor Mark Lindquist says he always advises law enforcement to get a warrant because “that’s the safe approach.”

McBride said he expects elected county prosecutors to adopt guidelines on special inquiries later this year.

Among them: Deputy prosecutors should get approval from a supervisor before using special inquiries, and courts should be reminded of their ownership of the proceedings — that judges aren’t there to rubber-stamp law-enforcement requests.

And what about the secrecy issue? Should people who have been targeted by special inquiry subpoenas be notified?

“It’s an interesting question,” McBride said. “I’m writing a note to myself to look at that.”