Mayor Annise Parker and City Council members are scheduled to vote Wednesday on a proposed final settlement with red-light camera company American Traffic Solutions.

However, there could be a new hurdle that prevents city leaders from approving the settlement as planned.

The U.S. 5th Circuit Court of Appeals issued a ruling Tuesday that gives leaders of the 2010 red-light camera referendum a right to intervene in the battle between the city and ATS.

"We should be able to intervene to defend the voters because if we don't defend the voters, the city will not," said Paul Kubosh after hearing about the court ruling.

Kubosh said he wants the mayor and City Council to amend the city charter to ban red-light cameras forever in the city of Houston, unless voters approve a change.

The proposed settlement between ATS and the city of Houston calls for the camera vendor to receive millions of dollars, but an amount less that it was seeking after the city terminated its contract.

"ATS is satisfied with the settlement. Potentially we can received up to $12.5 million," attorney Andy Taylor said. "Five million of which is guaranteed, that's meeting the city half way."

ATS originally went to court to seek a $25 million settlement.

The money from the proposed settlement would come from fines that have been paid by red-light camera violators and fines the city still hopes to collect.

"It's our position that if you look at the law, ATS is owned not one red cent," said Randall Kallinen, an attorney for the Kubosh family.

If and when the final settlement is approved, ATS has agreed to take down the red-light cameras within 60 days.