Bob Owens: The ATF director is going to talk. Whom will he implicate?

"Gunwalker: What Will Happen When Ken Melson Testifies?"

Melson will instead apparently testify in July about what he knows of the program of which he was “intimately familiar,” according to Issa. If Melson does testify as Solomon reports, several possible scenarios could play out:

1. Melson takes the fall.

While the Los Angeles Times reported that Melson didn’t want to take the fall for his superiors in the Obama administration, there still will be considerable pressure upon him to take the blame for the operation. There is a chance that he will use his time in front of Congress to either stonewall the investigation or to accept responsibility for having initiated and run Gunwalker.

If Melson was going to fall on his proverbial sword and take the blame for the operation, however, he had ample time to do so over the past two weeks. This is the least likely scenario.

2. Melson implicates Assistant Attorney General Lanny Breuer. Breuer takes the fall.

While the details of Operation Fast and Furious are still murky, it was to be run with the knowledge of the Department of Justice’s Criminal Division, run by Lanny Breuer. Breuer personally authorized a wiretap that was part of Gunwalker, and may have been responsible for blocking an ATF request to inform the Mexican government about the estimated 2,000 guns the operation let into their country. Breuer is no stranger to scandalous behavior, having represented President Bill Clinton during his impeachment and Sandy Berger after Berger stole classified documents from the National Archives.

Based upon what is known now about Gunwalker and Breuer’s loyalty to the Democratic Party, this appears to be the most likely scenario.

3. Breuer isn’t the highest link in the chain: Melson implicates Attorney General Eric Holder.

Chairman Issa states that AG Holder “absolutely” knew about Gunwalker earlier than he testified that he did, and if Issa has the evidence to prove that the attorney general is part of a cover-up, then there is every reason to suspect Holder will be forced to resign, or will face impeachment.

This is a far more likely scenario than many think.

4. Collateral damage.

There is the distinct possibility that Lanny Breuer and Eric Holder are not the only administration officials that run the risk of going down as a result of their roles in Gunwalker and its cover-up. While ATF and their parent organization the Department of Justice were ultimately responsible for the operation, other executive branch departments were involved.

The Department of Homeland Security played a role in Gunwalker, and DHS Secretary Janet Napolitano would possibly be kept abreast of Gunwalker since she was both the former governor of Arizona and the state’s attorney general from 1999-2002. Lesser-ranking figures within DHS and other agencies were certainly involved, but Napolitano is the cabinet-level official other than Eric Holder who would have most likely known about Gunwalker.

5. And they all fall down.

The least likely scenario is the most dramatic and explosive. There is the possibility that testimony from any of the above actors in this deadly drama could point directly to the Obama administration itself.

It is highly unlikely that the president would have known about the details of the operation unless it originated as one of his ideas. While this sort of devious plot is consistent with his policy goals — and his history of unethical gun control scheming is duly documented — layers of plausible deniability shield presidents from impeachment even if they are involved. It would take the figurative smoking gun — or perhaps a literal one, with Obama’s fingerprints on it — to acquire enough evidence to impeach the president.

In the unlikely scenario that the White House is implicated at all, a White House staffer would likely admit to being briefed about the generalities of the operation but not the specifics, similar to the way Congressman Issa was briefed that there was an ATF operation, but not that the ATF was effectively “walking” guns to the cartels.

We’ll know in several weeks if one of these scenarios comes to pass, or if something unexpected occurs to change the equation entirely.

One thing will not change: Hundreds have died as a result of a dangerous and illegal operation that occurred on President Obama’s watch, and someone is going to have to pay the price.