Prison escort firm Group 4 has been brought before magistrates for contempt after failing to deliver prisoners to court on time.
Group 4 was accused of disrupting court business
While on Monday, a spokesman for Northamptonshire Magistrates Court warned Group 4 that if it "disrupted court business" it could face further court action.
Last week, the company apologised to magistrates after Group 4 staff failed to deliver eight separate prisoners - who were due to appear for a morning session.
Jon Price, deputy clerk to the justices at Northamptonshire Magistrates Court, said Group 4 had been charged with contempt of court, but magistrates had accepted an apology from the company.
Fine or imprisonment
"Our view is they are supposed to provide prisoners before the court," he said.
"They need to produce these people.
"If significant problems recur, it is possible the court could hold them in contempt."
The penalties could include a fine or even imprisonment.
A spokeswoman for Group 4 said the failure to produce the prisoners on time was "most regrettable".
Extra funds appeal
She said: "We apologised to the court for the inconvenience that this caused."
She said the service for Northamptonshire had been hit by a shortage in the number of staff needed.
Group 4 are applying the Government for extra funds for staff in the Northamptonshire contract.
The spokeswoman added that Group 4 were also training extra staff.