Defense attorneys representing three members of the Datre family facing theft and fraud charges requested a mistrial and dismissal of the 492-count indictment Wednesday.

The court motions came a day after prosecutors admitted altering figures on certified payroll documents that were submitted into evidence during grand jury proceedings and into the indictment.

The development has delayed the start of the trial, which was scheduled to begin Tuesday with opening statements. State Supreme Court Justice Fernando Camacho has requested written letters from both sides Tuesday explaining why they believe the three altered documents do or do not challenge the integrity of unrelated counts in the indictment.

StoryProsecutors admit to marking evidenceStoryDatre lawyer: Town employees altered docsStoryJury selection to begin in town fraud case

The indictment alleges Clara Datre of Hauppauge and her children Gia Gatien of Hauppauge and Thomas Datre Jr. of St. James stole $148,504 from the Town of Islip through cleanup work billed after superstorm Sandy, and another $100,000 for failing to pay workers state-mandated prevailing wages for tree-trimming work done for the town on a separate contract. They have pleaded not guilty.

Last week, Andrew Campanelli, counsel for Clara Datre, said in court he believed Islip Town employees, under pressure from their bosses, altered information on key financial documents. Over the weekend, said Edward Heilig, the Suffolk County district attorney office's division chief, prosecutors went over the jury documents when Assistant District Attorney Leslie Stevens, who is also trying the case, realized they were her markings.

In court Tuesday morning, prosecutors admitted that Stevens used pencil markings on three certified payrolls to "make certain notations" when she was preparing the documents more than a year ago while making a presentation for a special grand jury impaneled last September.

advertisement | advertise on newsday

Kevin Kearon, attorney for Datre Jr., asked for a dismissal of the indictment without prejudice, as well as sanctions on Suffolk County District Attorney Thomas Spota's office and having Stevens disqualified from the case. Campanelli requested a special prosecutor replace Spota's office in trying the case.

"We're talking about an allegation of serious prosecutorial misconduct," Kearon said. "She made substantive changes to important factual components of those documents, changing dates, changing invoice numbers."

Heilig said Stevens "made a mistake."

"I think what's happened here is that we're blowing this way out of proportion," Heilig said in court.

Prosecutors have offered to drop six counts, including falsifying records and offering a false instrument for filing, and lower a seventh count relating to prevailing wage from a D felony to an E felony. Stevens did not speak in court during the past two days and she and Heilig declined to comment outside of court both days.

Campanelli said Stevens crossed out the work order number on one document and "physically changed" the date of the other payroll records before submitting them to a grand jury. He also alleged in court for the first time Wednesday that in addition to certified payroll records being altered, employee punch cards were altered with ink, marker and white-out.

"This was not an oversight or mistake," Campanelli said. "These were deliberate alterations to actual evidence. She submitted this to the grand jury."