Ellison could not be reached for comment. Board President Neil Campbell said he was disappointed by the prosecutor's assertions and disputed that the board had been trying to stifle the investigation.
"The board, acting on the advice of our counsel, will continue to provide information and continue to fully cooperate as we have been doing since the outset," Campbell said in a statement Monday night.
Earlier this month, Campbell expressed confidence in Ellison. He said the solicitor's firm, Rhoads & Sinon, has raised its hourly fee just once in a decade - to $180 - and had saved the district almost $4.6 million since 2008. "The taxpayers of this district have been very well served by our solicitor," Campbell said.
The district attorney, however, said other districts spend far less on their solicitors, without elaborating. "The only thing we've seen so far is the solicitor has cost this school district millions of dollars," Hogan said.
Hogan's criticism marked the latest turn in the text-messaging scandal that has engulfed the 7,200-student district for nearly two months.
The school board is searching for a new superintendent after the discovery of racist and sexist text messages on the district-issued phones of former Superintendent Richard Como and athletic director James Donato led both men to resign.
In the wake of those messages, board officials said Hogan's office was investigating potential kickbacks involving high school athletic camps in the district. The camps were referenced in the text messages.
The texts were discovered this summer by Abdallah Hawa, director of technology for the school district, and Teresa Powell, now the acting assistant superintendent.
In his statement, Hogan accused the board of harassing Hawa and Powell since the texts and their roles became public.
In an interview Monday, Hogan said the district tried to prevent Powell from cooperating. "They called her in and told her to provide them with everything they wouldn't give to us or she'd be terminated," Hogan said.
The school district, he said, also reneged on a promise to make people available for interviews.
Reached Monday afternoon, Hawa said acting Superintendent Angelo Romaniello Jr. sent him an e-mail a few weeks ago telling him not to release any documents without first going through the solicitor. He also said board members had kept him and Powell from doing their jobs fully.
But Hawa said the district attorney's statement gave him hope that the Coatesville school system can get back on track.
"I was worried there for a while. I feel a little bit better now," he said. "It's been a nightmare here. They really put us through hell, me and Dr. Powell. And they continue to do that. Now, hopefully, they'll stop doing that."
Romaniello declined to comment. His lawyer, Robert J. Donatoni, said Romaniello had cooperated with the investigation, but declined to talk specifics.
Samuel Stretton, the attorney representing Hawa and Powell, said the prosecutor's statement reinforced claims he has made for weeks.
"The district's got to get rid of the solicitor or nothing's going to change," Stretton said. "Maybe now things will finally start to happen for the better in the district."
Campbell disputed parts of Hogan's statement. He said the district had turned over documents to prosecutors and "directed all employees to cooperate fully" with the probe.
Hogan also said Ellison could no longer represent the district because he and his firm are part of the investigation. But the school board could also dispute that there is any conflict of interest, he said.
The prosecutor said he had never encountered such a lack of cooperation from a public agency.
"We've had to investigate other public entities. Those other entities have always been very straightforward and wanted to get to the bottom of what was going on," Hogan said. "I have never had to publicly talk to a taxpayer-funded body who was not cooperating with us."
The school board is scheduled to meet Tuesday night. Hogan said board members have to decide if they will cooperate.
"At the end of the day, the commonwealth will discover the full truth," the prosecutor said. "The only question is whether the [school] board will help or hinder this process."