In compliance with a federal integrity agreement, pharmaceutical giant Pfizer released details of its financial involvement with the medical community.

According to the New York Times, the drug maker disclosed that it paid $20 million in consulting and speaking fees to 4,500 doctors in the second half of 2009. The company also shelled out $15.3 million to U.S. academic medical centers for their clinical trials.

A few other drug makers have disclosed their payments to physicians in the past, but this is the first time a company has disclosed its payments for clinical trials. As such, some may see this as a good deed on Pfizer’s part, a noble step towards eliminating or reducing some of the conflicts of interest in medicine.

Only, disclosure doesn’t seem to help. Several studies have shown that when professionals disclose their conflicts of interest, this only makes the problem worse. This is because two things happen after disclosure: first, those hearing the disclosure don’t entirely know what to make of it — we’re not good at weighing the various factors that influence complex situations — and second, the discloser feels morally liberated and free to act even more in his self-interest.

So, in this case the people who run Pfizer will likely feel even more entitled to disregard the public good, and the public, in turn, will not know what to make of the numbers it released. After all, what do you make of the numbers? It’s hard to figure out from a statement of disclosure just how much influence the conflict of interest had on the discloser, and to what degree we should be wary of them as a result.

The real issue here is that people don’t understand how profound the problem of conflicts of interest really is, and how easy it is to buy people. Doctors on Pfizer’s payroll may think they’re not being influenced by the drug maker — “I can still be objective!” they’ll say — but in reality, it’s very hard for us not to be swayed by money. Even minor amounts of it. Or gifts. Studies have found that doctors who receive free lunches or samples from pharmaceutical reps end up prescribing more of the company’s drugs afterwards.

It’s just a fact of human life: we are compelled to reciprocate favors, and an ingrained inability to disregard what’s in our financial interest. As author Upton Sinclair said, “It is difficult to get a man to understand something when his salary depends upon his not understanding it.”