So tell me about the Mahon tribunalIt was set up 15 years ago to investigate planning corruption.

Fifteen years? That's a long timeYes, it got bogged down a bit. First it had lots of allegations to examine, starting with the former minister Ray Burke. Then there were court challenges and various delays. When the hearings began at Dublin Castle they moved at a snail's pace for years. Three new judges were brought in after the original chairman retired.

Did anything happen?A developer, Tom Gilmartin, came forward with allegations of political corruption at the highest levels. And a former government press secretary, Frank Dunlop, fessed up to his role as a bagman for developers. Dunlop paid county councillors cash in return for their votes on rezoning motions at the council. The developers made fortunes when their lands rocketed in value after being rezoned for housing. Everyone was happy.

Everyone?Well, no, the rest of us got bad planning, ghost estates and inadequate services.

How did Bertie Ahern get caught up in all this?Gilmartin said another developer told him he paid money to Ahern. The tribunal investigated Ahern's finances. They weren't very happy with what they found: large amounts of money were going through his accounts in the 1990s for which no satisfactory explanation was given. Ahern says they were dig-outs from friends after his separation, but the tribunal says he's lying.

So is he just as corrupt as the rest of them?No. The tribunal did not make a corruption finding about Ahern. It said he didn't tell the truth about his accounts, but it was unable to say where the money came from.

Will anything come out of all this?Burke and Dunlop have already spent time in jail. About €50 million in extra tax has been raised from those investigated by the tribunal. Now the report, published on Thursday, has identified 14 politicians who were corrupt. The list includes the former minister Pádraig Flynn; he took €50,000 and used it to buy a farm instead of giving it to Fianna Fáil.

Will heads roll?Don't bet on it. Some of the corrupt councillors are dead. One developer has already said that he will challenge the report findings in the courts. The report is being sent to the Garda, but previous Garda investigations don't inspire confidence.

Isn't it all there in black and white, though?The judges' findings are based on the balance of probabilities. That won't suffice in a courtroom, where something has to be proved beyond reasonable doubt.

Who's paying for this?You and I. The tribunal is expected to cost €250 million, but it could be much higher. The tribunal's senior counsel were earning more than €2,000 a day for several years. Other parties' bills will roll in for years to come.