The federal trial of a Masury man is scheduled to begin this morning in Pittsburgh for his alleged role in a multiyear scheme to defraud a Sharon-based regional healthcare nonprofit of more than $2 million.

John O’Brien, 63, is the final defendant to go to trial in a case involving the Primary Health Network. The organization is a nonprofit that provides medical services to underserved communities. While four other men charged in the investigation have already entered guilty pleas, O'Brien has maintained his innocence.

The proceedings are being held before U.S. District Judge J. Nicholas Ranjan at the United States Courthouse. The trial is expected to last approximately three weeks.

O’Brien faces one count of conspiracy to commit mail and wire fraud and three counts of wire fraud. The charges were brought by a federal grand jury in May 2023 and updated in a superseding indictment in March.

Federal prosecutors allege that between 2011 and 2019, high-ranking officials at the health network used their positions to steer funds toward themselves through deceptive business practices. O’Brien specifically controlled a company called Tele-Data. Investigators claim this company was used as part of the scheme to drain money from the nonprofit.

Unlike his former co-defendants, O’Brien entered a plea of not guilty to all charges. He has remained free on a $100,000 unsecured bond while awaiting today's start of the trial.

Today’s trial follows a series of guilty pleas from other leaders involved with the Primary Health Network.

Drew Pierce, age 58, of West Middlesex, Pennsylvania, a former chief executive of the network, pleaded guilty in October 2025 to conspiracy charges. As part of his plea agreement, he accepted responsibility for more than $3.1 million in restitution owed to the health network. He is scheduled to be sentenced in March.

John Laeng, age 72, of Lake Milton, another former chief executive, pleaded guilty in September 2025. He was ordered to pay nearly $2 million in restitution. Mark Marriott, age 58, of Sharpsville, the former facilities manager, pleaded guilty in October 2025 to fraud and tax-related charges.

A fourth man, Christopher O’Brien, age 61, of Masury, who owned a construction company, also pleaded guilty to fraud conspiracy in early 2024. His sentencing has been delayed several times and is currently set for next month.

In the weeks leading up to today, the judge ruled on several requests to limit what evidence the jury can hear. While the judge agreed to block some evidence related to other construction projects, he ruled that prosecutors could present information about O’Brien’s personal finances and past legal issues.

According to court documents filed last week, the jury will be told that O’Brien was involved in a difficult and long divorce starting in 2015. Additionally, the jury will hear that O’Brien and his business owed more than $180,000 in unpaid taxes to the government as of 2016. Prosecutors may use the information to argue that O’Brien had a financial reason to take part in the alleged fraud.

Once the jury is selected, the government and the defense will give their opening statements.

Court filings suggest as many as 40 people could testify for the government. The witnesses may include former employees of the health network and experts who can explain bank records and contracts.

The jury will also look at documents, such as emails and bank statements.

Because this is a federal criminal trial, the verdict must be unanimous. If found guilty, O’Brien could face a prison sentence of up to 20 years on the most serious fraud counts.