The solicitor was shot dead at his Belfast home in front of his family by members of the outlawed UFF in February 1989.
Addressing Derry City & Strabane District Council, the Ballyarnett representative said: “Pat Finucane’s murder was one of the most controversial and notorious of The Troubles.
“Not only because of the manner of his murder where he was gunned down in his family home in front of his wife and three children, but also because of the clear evidence of collusion with not much evidence of any investigation.
“And that’s not my opinion, that’s the considered opinion of respected judges and lawyers.
“The UK Supreme Court said the murder investigation was inadequate.
“The Stevens Inquiries found evidence of collusion between security forces in the murder. The De Silva report confirmed evidence of collusion and state agent involvement in the murder.”
Councillor Farrell addedL “Brandon Lewis, the Secretary of State himself, when announcing that the inquiry would not proceed said the “levels of conclusion were totally unacceptable”.
“In my view any collusion is unacceptable.
“State agents are state employees. They’re supposed to protect and help people, not murder them.
“The British government is responsible for the actions of its agents, but they don’t want an inquiry as it will expose the levels and the extent of collusion in Pat Finucane’s murder.
“If they have nothing to hide, they should have nothing to fear.
“The SDLP supports the Finucane family in their search for truth, their fight for justice and their demands for an inquiry.”