Yesterday Credit Suisse First Boston, the last of ten banks embroiled in an investigation into questionable Wall Street practices, agreed to revamp its research department and pay fines to compensate investors caught up in the whole sorry affair.

The news marks the end of a one-man campaign to clean up Wall Street, a campaign that has pitted the New York attorney-general against some of the most powerful men in finance.

On Monday Spitzer will fly to Washington where he will present details of a deal with the miscreant banks to Capitol Hill.

Under the terms of the settlement, the banks will overhaul a once highly profitable arrangement that linked analysts’ recommendations to the performance of the bank’s corporate advisory teams. They will also agree to “buy-in” research from rival firms and to police their own stock pickers with internal monitors.

The settlement will cost jobs, as well as hard cash. But Spitzer denies suggestions that he is a one-man wrecking ball, intent on wreaking havoc on the Street.

“It’s hard to imagine that research could get any worse,” he scoffs. “The fact of the matter is, what they were recommending we buy was . . . junk. (The banks) had created an incentive structure that was perverse, that completely undermined the objectivity of the research.”

In an exclusive interview with The Times, the 63rd New York attorney-general takes a moment to show off the view from his 25th floor office at 120 Broadway.

“It used to be better,” he remarks. On one side his office overlooks Broadway stretching north like a vast yellow-spotted conveyor belt. To the west it surveys the “pit”, where the Twin Towers formerly stood.

Vast lengths of window sill and shelf space are crammed with photographs of his three daughters, their playful poses, fuzzy jumpers and Hallowe’en pumpkins, providing a sharp contrast to the stamp of office that sits above his stately desk.

That Spitzer’s people have bought plane tickets to Washington is the hardest proof yet that the deal is going through on Monday, following a process that has been dogged by hold-ups. Waiting for the global settlement has been, as an SEC representative joked the other day, “like waiting for a baby”.

Spitzer launched his campaign into Wall Street after a disaffected client successfully sued Merrill Lynch, one of the biggest firms in the world’s financial markets, over the poor quality of its research.

“To a certain extent, we found the needle in the haystack with e-mails, which laid bare (the activities of Merrill Lynch) in a somewhat crasser way than people were expecting.”

Times Recommends

• Darling under pressure on record public debt
• Mortgage drought deepens on 32% lending fall
• Oil prices firm after 10% drop to below $130