Frank Minal, GMB union regional officer, is looking at taking action over the conduct of St Joseph's School chair of governors, Father Kevin O'Driscoll, after he suspended Kevin Jones, headteacher, Victor Crewes, bursar, and Hannah O'Toole, head of IT, on Monday.
An investigation into the scam, which has left the school stranded in thousands of pounds of debt, is now under way.
Mr Minal said: "It's absolutely disgusting. There are in excess of a hundred schools in this position across the country and there haven't been suspensions as a result of it. Naming then implies some form of wrongdoing. We are looking at taking action against the school's conduct."
The school signed up for IT equipment that was offered to them for free. However, they were actually duped into committing to mis-sold lease agreements.
Father O'Driscoll said: "Incidents across the country vary in seriousness.
"The school has ended up in this position and we need to find out why.
"We wanted to be honest and open with parents and the media and wanted to protect the other teachers at the school.
"Suspension is a neutral act and in no way implies guilt."
Slough Borough Council legal experts have been called in to offer the school advice. Speaking earlier in the week Father O'Driscoll said: "The education of the children at our school is paramount and we will be working hard with the teachers at the school to ensure pupils learning is not disrupted."
The council confirmed it was not aware of any other Slough schools being targeted.
A Department of Education representative said: "Parents expect heads to be absolutely professional and thorough in their financial management, particularly in negotiating complex leasing deals. We've worked with a wide range of organisations to give schools clear advice on how to get the best value for money.
"The bottom line is that if a deal seems too good to be true, it probably is. Schools need to be absolutely sure of what they sign up to and read the small print."