In the name of fighting crime, government prosecutors have tremendous power to investigate, charge, and sue those suspected of wrongdoing. But that power can lead to abuse.

Easy access to favorable publicity lures ambitious prosecutors into pursuing politically popular cases, even if those cases aren’t always legally sound. And prosecutors can be tempted to use their posts to further their own political or ideological agendas.

New York Attorney General Eliot Spitzer increasingly appears to have succumbed to both temptations.

After attracting sensational attention for pursuing tobacco companies and Wall Street, Spitzer is continuing his prosecutorial crusade against "big business."

Labeling himself the "people’s lawyer," Spitzer has turned to new targets in an effort to make an even bigger splash before formally beginning his campaign for Governor of New York. But as Spitzer has widened his net, his cases have gotten thinner and his motives have grown increasingly suspicious.

Last month, in a classic example of regulation by prosecution and after declaring drug manufacturers would be his next corporate targets, Spitzer filed a lawsuit against drug-maker GlaxoSmithKline, charging that the company withheld negative information about one of its drugs from doctors and consumers.

His lawsuit attracted world-wide attention, and once again landed Spitzer on newspaper front pages, this time attacking politically unpopular drug manufacturers. Unfortunately, Spitzer’s case threatens to undermine the carefully woven fabric of regulation that ensures the quality and safety of drugs across all 50 states.

By mandating through his suit what information drug makers must provide doctors, Spitzer substitutes his regulatory judgment for that of the Food and Drug Administration — the only governmental agency tasked with drug regulation — which has existing rules addressing precisely the kind of communications that Spitzer’s suit attacks.

Spitzer was not elected to regulate the drug industry, and his interference with the federal government agency specifically mandated to do so constitutes a gross abuse and substantial expansion of his power.

Meanwhile, just days after beginning his foray into prescription drug regulation, Spitzer sued Dick Grasso, former New York Stock Exchange CEO, and Ken Langone, an investment banker and former NYSE Board Member.

This time, Spitzer appears to have yielded to an urge to renew his attack on Wall Street and insert himself into a high visibility contract dispute. While the suit has generated tremendous media coverage, Spitzer’s actual legal case appears thin.

Many legal experts believe Spitzer will have a hard time proving his main contention — that Grasso and Langone broke a New York law governing executive compensation at non-profit organizations. At the same time, the selective pursuit of Grasso and Langone reveals Spitzer’s motives to be less than altruistic.

Grasso was fired by the NYSE after criticism of his compensation package. Spitzer says Grasso misled the NYSE Board of Directors into approving the package and wants Grasso to return the money to the Exchange.

Langone, a widely respected investment banker, was Chairman of the NYSE Board’s Compensation Committee when it developed Grasso’s compensation package. Spitzer says that Langone helped mislead the Board into approving Grasso’s pay structure, particularly a provision related to deferred compensation.

Spitzer, however, neglected to charge Carl McCall, who took over the NYSE Compensation Committee from Langone and personally urged the Board to approve making the deferred payments to Grasso. Prior to joining the NYSE Board, McCall was New York State Comptroller and remains a leading figure in the state Democratic Party. As such, McCall stands to be a key figure in Spitzer’s developing campaign for Governor of New York.

Both Grasso and Langone vigorously deny Spitzer’s charges. Among the arguments they make to refute his claims, Grasso and Langone point out that every member of the supposedly "duped" NYSE Board had a complete copy of Grasso’s compensation package and a report detailing its provisions in plain English. They also point out that most of the Board members were Wall Street luminaries who had negotiated similar, complex compensation packages for themselves.

Such is the nature of Spitzer’s overreaching for personal and political gain. Still skeptical? Consider this: even if Spitzer wins his suit on all counts, Grasso and Langone would pay damages to the NYSE, not the state of New York. Thus, New York taxpayers are funding Spitzer’s pursuit of a questionable case which can benefit only the New York Stock Exchange and Spitzer.

Spitzer’s record of taking on big business has helped him establish a public persona as a courageous crusader. His most recent cases have begun to reveal his true nature: a self-promoting, political opportunist. That hardly makes him unique. But his willingness to expand and abuse his prosecutorial power to achieve political objectives makes him dangerous.

This commentary originally appeared in the Albany Times-Union.