Maghull Labour Councillor Patrick McKinley said Sefton's decision to reject plans for a 'care village' on Damfield Lane was a "victory for common sense".
Sudell Ward Labour Councillor Patrick McKinley spoke on behalf of residents at Wednesday's planning committee meeting when the plans were rejected.
News that plans had been submitted for a major care village in Maghull came to light during the summer.
As soon as they discovered the plans, Maghull Labour Action Team's Cllr McKinley, Lynn Gatherer and Cllr Steve Kermode organised a consultation meeting to give members of the public the chance to see the plans for themselves.
The Labour Councillors also helped the residents form the action group.
Cllr McKinley said: "This is a victory for common sense.
"The social costs of a development like this are too great and adversely affects the sense of place and well being for Maghull residents.
"This may be the first skirmish in a struggle to protect our Greenfield and Greenbelt. It demonstrates that if we stand together and are united we can fight to protect the way of life for Maghull residents against the narrow self interest of unfettered development."
Maghull Labour Action Team's Lynn Gatherer said the residents had put a strong argument against the plans.
Lynn said: "As soon as we found out about these plans we made sure the residents were informed and they had the chance to have their say about the plans and contribute to the ultimate decision.
"The residents put together a brilliant case and my Labour colleague Cllr Patrick McKinley put the case to the planning committee who thankfully listened to the points raised.
"Throughout this issue, the Labour Action Team has acted in the interests of the community, but since news of the plans came to light last summer, we have discovered that the Liberal Democrats in East Sefton had been aware of the plans for more than two years without raising the issue with the community.
"They should be ashamed of themselves for sitting on such information and not sharing the details of the plans with the community who it would directly affect.
"The Labour councillors on the planning committee voted against these plans, but it is concerning to note that there were Liberal Democrats on the planning committee who voted in favour of the care village despite the concerns of residents.
"The Labour Action Team will continue to work and fight for the interests of the community."
Speaking in Parliament following the planning committee’s decision, Sefton Central Labour MP Bill Esterson slammed Lib Dem councillors who voted in favour of the development against the community’s wishes.
Bill said: “Developers in my constituency are queuing up to build on green-belt land and on urban green spaces, encouraged by the Government’s new planning framework and supported by Tory and Lib Dem councillors as recently as in yesterday’s planning committee meeting.
“My constituents want to know whether they have any chance of defending themselves against such developments?”