It would appear that similar cases are being treated very differently, perhaps due to self-interest and partisanship on the part of Bush officials, i.e., hypocrisy. But are the circumstances in fact similar? With the Marc Rich pardon (among others), credible allegations were made of an improper quid pro quo: Rich people gave money to Democratic groups, and the Democratic President gave out indefensible (and otherwise inexplicable) pardons. In the case of Enron, no quid pro quo has even been alleged; the Democrats haven’t even decided whether it’s a better tactic to attack Bush for doing too much for his big Enron contributors, or to attack Bush for doing nothing to help Enron.
The Bush Administration of course has written rules concerning energy firms, and they have been characterized as more favorable to the energy firms than one would expect from, say, a Gore Administration. But this was no secret, it is absurd to think it was due to Enron contributions, and in fact the differing energy positions of Bush and Gore were widely commented upon during the last election. More to the point, the collapse of Enron was not due to any Bush rules; it was due to Enron’s opaque accounting, which hid large debts which were still effectively held by the firm. Insofar as the federal government has a responsibility for this, Enron’s actions were made possible by weak accounting rules and enforcement during the Clinton Administration, albeit perhaps more due to the actions of Congressmen of both parties than to the actions of any Clinton officials.
In short, while there are strong grounds for subpoenaing Enron officials and auditors, and perhaps grounds for subpoenaing various Congressmen about accounting rules changes, and even Bush Administration officials concerning Enron’s pleas for help as its situation unraveled, there are essentially no grounds for subpoenaing Cheney's energy task force records. Politicians constantly vote or write laws or policies affecting campaign contributors. If the Bush Administration is effectively forced to release records of its meetings with Enron officials concerning energy policy, then no President, and indeed no Congressman, can ever again expect to privately meet with a constituent.