The Liberal Democrat councillor who publicly campaigned against his own party over the Beddington incinerator project has been expelled from the group for bringing it into disrepute.

RELATED: Lib Dem who opposed Sutton Council's incinerator plan suspended

Councillor Nick Mattey faced a conduct hearing at Liberal Democrat headquarters in London last week where it was agreed he publicly opposed a decision taken by the council to build the incinerator and had actively campaigned against Liberal Democrat candidates in public elections.

Coun Mattey said he was not shocked by the decision and would be appealing it.

He added: “It was a regional inquiry so there was always a chance that I would be expelled but now I have an opportunity to appeal to the national party.”

Coun Mattey was suspended in April last year after making public a 1,500 word letter in which he backed the ‘stop the incinerator campaign’.

In the letter he criticised his fellow Lib Dem councillors for standing "shoulder to shoulder" with Viridor and urged councillors to “forget behaving as a group and to begin to think independently and critically”.

A letter sent to Coun Mattey informing him of his expulsion read: “The decision regarding the energy recovery facility at Beddington Lane had been taken before you were elected to the council and that the decision had been taken by the Lib Dem administration.

“You were fully aware of this at the time of your election. Following your election you became increasingly outspoken in your attempt to overturn this decision including allegations of impropriety and corruption.

“The group worked hard to accommodate your deeply held views on incineration but unfortunately these overrode your wider responsibility to the group and the party leading to your suspension.”

It also upheld a complaint Coun Mattey distributed political flyers containing “strong anti Lib Dem messages and anti-incineration messages” to support his son in a by-election.

The expulsion means Coun Mattey is barred from standing for election to public office should he re-join the party.

He has until February 12 to appeal.