The odds of a joint action against the federal government's Centrelink debt recovery program have narrowed, with lawyers saying it's considered highly unlikely such an action would succeed.

However, Slater and Gordon – and perhaps some of Australia's other leading class action law firms – are investigating Centrelink's handling of the scheme, and have not ruled out challenging the legality of its conduct under Commonwealth laws.

Slater and Gordon practice group leader Tim Finney told Fairfax Media that individuals could have grounds to appeal the validity and legality of debt notices sent by Centrelink.

"Slater and Gordon is currently reviewing Centrelink's conduct for the purpose of confirming whether it has engaged in any contraventions of applicable laws," Mr Finney said.