This announcement comes after an 18-month investigation, in which a grand jury looked into Montgomery County politics and found a lot wrong with the way things are run.
None of the questionable practices are actually illegal. However, the investigation did find that Commissioner Matthews broke the law.
He was arrested in Springfield Township Tuesday morning and faces up to nine years in prison on charges that he lied to a grand jury during the investigation.
Through his attorney, Commissioner Matthews denied the charges.
Montgomery County District Attorney Risa Ferman called on the grand jury back in 2009 to look into five different areas of concern.
Those areas include:
-how county commissioners used campaign funds
-the county's competitive bidding process
-whether commissioners held meetings in violation of sunshine laws
-how the county's open space program spent money
-the relationship between Commissioner Matthews and a company called Certified Abstract, which had an exclusive contract to do title work for the county.
In its 69-page report, the grand jury found a number of concerns, but said none of those rose to the level of illegality under current law.
Ferman said the grand jury didn't find anything illegal until they called Commissioner Matthews in to testify.
"The grand jury found that Commissioner Matthews' lies were so prevalent during his testimony - so blatant - that he felt it was his right to do so as the chairman of the Board of County Commissioners," Ferman said.
The report suggested charges be brought against Commissioner Matthews, alleging that he lied about his business relationship with Certified Abstract and about whether he'd spoken to people about his grand jury testimony.
At his arraignment, the commissioner was released on $50,000 bail.
Commissioner Matthews is also the brother of cable news commentator Chris Matthews.
The Associated Press contributed to this report.