I'm assuming contingency because if the model is the tobacco lawsuits, there are a few lawyers who became multi-millionaires from the settlement, a couple, possibly even billionaires. Hourly work doesn't get you that. Even assuming contingency, likely costs of litigation would be billed to the city along the way. These include, essentially, everything expended on the lawsuit, but not attorney fees.
...but it depends on how you look at it. Assuming that the city has been damaged in some way by these manufacturers and has had to expend funds to deal with the crisis, the lawsuit, ostensibly, would be to recoup those damages....which were paid for by tax dollars. In other words, the money is already gone. Since government never has any money of its own, no new taxpayer money may be spent, but anything recovered is really the taxpayer's money...that they will never see.
