Three top city prosecutors, including Keith Kaneshiro, should go on leave because of a taint created after the three reportedly received letters from the federal government linking them to a wide-ranging public corruption probe, according to criminal defense attorneys, a City Council member and a California law professor.

Councilman Ron Menor, vice chairman of the Council’s Public Safety Committee, told the Honolulu Star-Advertiser that he agrees that the three most recent letter recipients should go on leave pending resolution of the matter.

“It is important for government officials serving in important law enforcement positions to be above reproach and maintain the highest standards of integrity,” Menor said.

If the three don’t go on leave, public confidence in the office could be undermined, he added.

Peter Carlisle, Kaneshiro’s predecessor, went a step further, saying Kaneshiro should immediately resign to help restore public trust in such a critically important law enforcement body.

“I don’t know how you can have confidence in that office right now,” Carlisle said. “This unfortunately gives a black eye to all the good people working there.”

The prosecutor’s office did not respond Monday to Star-Advertiser requests for comment.

Hawaii News Now reported Monday that Kaneshiro received what is called a target letter from the U.S. Department of Justice, informing him that he is under investigation in an ongoing corruption probe that already has resulted in the indictment of former Police Chief Louis Kealoha; his wife, former Deputy Prosecutor Katherine Kealoha; and four former or current police officers.

The news organization also reported that two top deputies, Chasid Sapolu and Janice Futa, received what are called subject letters, not as strong as target letters.

The U.S. Attorney’s Office in Honolulu did not respond to a request seeking confirmation that the letters were sent.

Target letters typically specify that the recipients are under investigation, and law enforcement experts say a target letter is an indication that the recipient is expected to be indicted.

Investigators usually tell subject-letter recipients that they are suspected of misconduct but more investigation is needed, experts say. For law enforcement officials to get either type of letter is a serious matter, experts say.

Kealoha placed himself on leave as police chief after getting a target letter about two years ago, while the officers who received such letters were placed on leave. Katherine Kealoha already was on leave when she received her letter but remained on the prosecution staff until September, when she resigned.

All of the recipients subsequently were indicted.

A spokesman for Mayor Kirk Caldwell said the mayor believes the prosecutor’s office should cooperate with any Justice investigation and address any improprieties immediately. He did not say whether Caldwell supports calls for the three prosecutors to go on leave.

“The mayor respects the procedures that are in place under our federal and state constitutions to ensure that due process rights are observed,” Caldwell spokesman Andrew Pereira said in an email. “We should allow the time it takes for those actions to occur so that justice is served.”

The revelations of the new letters could present opportunities for criminal defense lawyers whose clients were prosecuted by any of the three to raise questions about the integrity of the office and potentially seek dismissals of charges or overturning of convictions, according to legal experts.

“I would think (defense attorneys) would want to make something of this,” said Greg Keating, a University of Southern California Gould School of Law professor who teaches professional responsibility courses.

“Your integrity has been questioned by someone with authority to do so,” Keating added. “That casts a cloud over everything you do.”

Victor Bakke, a criminal defense attorney, said he already is preparing a motion to have a client’s murder conviction reversed based on Sapolu’s involvement in the case. Sapolu helped prosecute Dae Han Moon, who was found guilty recently of the Christmas Day 2016 murder of Steve Feliciano at Ala Moana Center.

A judge already found that the prosecutor’s office committed misconduct by failing to disclose relevant information to the defense in that case, according to Bakke. The court ruled that information a witness told Sapolu about a knife should have been turned over to the defense but wasn’t, Bakke said.

Now that Bakke knows Sapolu received a subject letter, the defense attorney said he intends to seek a copy of the letter — which federal authorities usually don’t release — to determine whether the conduct Sapolu is being questioned about has a bearing on Moon’s case.

“Every case he touches is tainted,” Bakke said.

If the prosecutors are accused of misconduct involving their duties as law enforcement officers, as opposed to something like cheating on taxes, the misconduct allegations could be used to question their actions in any of the cases they helped prosecute, according to criminal defense attorney Jonathan Burge.

“This puts a very dark shade over their office,” Burge said. “It’s a pretty big deal.”

Carlisle said he would expect defense attorneys to file many such challenges. “There’s not the slightest doubt,” he said.

KEY EVENTS IN THE KEALOHAS’ CASE

>> Nov. 18, 2009: Capt. Louis Kealoha selected as Honolulu police chief.

>> Oct. 11, 2010: Keith Kaneshiro sworn for his second stint as Honolulu city prosecutor, some 14 years after leaving the office.

>> June 22, 2013: Deputy City Prosecutor Katherine Kealoha, the wife of Police Chief Louis Kealoha, reports to police that the mailbox has been stolen from in front of the family’s Kahala home.

>> June 29, 2013: Kealoha reports that her uncle Gerard Puana was captured on home surveillance video stealing the mailbox. The Honolulu Police Department turns over the case to the U.S. Postal Inspection Service.

>> July 1, 2013: Federal prosecutors charge Puana with destroying a mailbox, a crime punishable by up to three years in prison and a fine.

>> Dec. 4, 2014: On the first day of Puana’s trial in U.S. District Court, Louis Kealoha identifies the person in the video as Puana but causes a mistrial by telling the jury about Puana’s 2011 conviction for unlawfully entering a neighbor’s home. Alexander Silvert, Puana’s defense attorney, accuses Kealoha of purposely causing the mistrial to avert a not-guilty verdict that would have undercut Katherine Kealoha’s standing in a civil case against Puana.

>> Dec. 17, 2014: Silvert says he has turned over information about the mailbox theft case to the FBI for investigation. This eventually triggers a federal grand jury query about alleged police misconduct, which leads to an investigation centering on the Kealohas and others.

>> Dec. 20, 2016: Chief Kealoha places himself on voluntary paid leave after the FBI sends him a “target letter” informing him that he is the focus of a criminal investigation. Deputy Chief Cary Okimoto is appointed acting chief.

>> Jan. 6, 2017: Police Commission Chairman Max Sword announces Kealoha has agreed to retire, ending a 33-year career.

>> Jan. 13, 2017: FBI agents serve the Honolulu’s Prosecutor’s Office with a search warrant. Kaneshiro objects to the search, saying the laptops’ seizure could affect ongoing criminal investigations.

>> Feb. 28, 2017: Kealoha officially retires from HPD.

>> May 9, 2018: A judge sets Nov. 14 for the start of the Kealoha trial on charges the Kealohas lied on loan applications to secure mortgages from banks. The judge sets March 19 for a second trial on charges of staging the theft of their mailbox to frame Katherine Kealoha’s uncle in a family dispute over money and lying about it to federal investigators or the grand jury.

>> Sept. 17, 2018: Katherine Kealoha resigns as deputy prosecutor with the City and County of Honolulu.

>> Oct. 23, 2018: A judge postpones the Kealohas’ Nov. 14 trial date after reviewing Katherine Kealoha’s medical records.

>> Oct. 25, 2018: A judge moves the Kealohas’ bank fraud trial to June 18. The Kealohas are set to stand trial March 19 for the mailbox case.