According to the failed bailout bill, with the president's approval, the treasury secretary's spending cap can be raised to $350,000,000,000.00. The cap can be further raised to $700,000,000,000.00 by issuing a plan to congress, and congress has 15 days to issue a resolution rejecting the plan, otherwise it is allowed to proceed. (Section 115)
The treasury secretary is allowed to make up his own rules as far as conflict of interest goes. (Section 108)
Oversight is provided by a congressional oversight panel, which is allowed to inspect what the treasury secretary is doing and issue reports (Section 125), and judicial review. The judges can intervene if the treasury secretary is breaking any laws or is deemed to be acting in an arbitrary fashion or is abusing its power (Section 119). The comptroller general (whoever that is) is also allowed to make audits and report problems. If a problem is reported, the treasury secretary is required to either correct the problem or "certify to appropriate committees of congress that no action is necessary or appropriate".
Henry Paulson is a former CEO of Goldman-Sachs and is likely to personally benefit from the bailout. I don't profess to know if he would allow that to influence his actions, but it does raise some suspicions.
http://online.wsj.com/public/resources/documents/bailoutbill20080928.pdf
(I'm not a lawyer, and I haven't read the full text, so I may be missing or misrepresenting some important details.)
Discussion (1)
I'm sure he's probably an exec on plenty of other boards.