No, he wasn't. Or more accurately, there is no evidence that he was, and a sworn officer of the court has publicly stated he was not.
Somehow, two convicted felons can't "possibly" be lying, but a federal prosecuter is assumed to be lying through his teeth, even when there's no reason for him to do so (because, for example, whether or not the drug smuggler was arrested again for drugs is completely irrelevant to the guilt of the border patrol agents.
But the BP supporters are willing to insist the guy was arrested again, but all evidence of the arrest has been purged, and every person involved is now involved in a grand conspiracy to hide this arrest, for absolutely NO REASON WHATSOEVER. Which of course is perfectly believable to the pro-BP-agent crowd, who think people would risk years in prison for lying just to make the prosecuter not look silly.
There is a non-zero probability that the BP agents were telling the truth. But the hysterical rantings of the pro-BP agents, callign other BP agents liars, crooks, calling prosecuters liars, suggesting the Bush administration planted people in these offices for the purpose of giving aid and comfort to drug smugglers and railroading BP agents, pretty much makes a mockery of whatever credibility these two BP agents might have had.
We have the official, signed statements of the two BP agents which contradict their own testimony. That alone makes their credibility suspect, before we ask a single question of ANY other witnesses.
Sutton foolishly went out on a limb for the sake of the drug trafficker and Aldrete-Davila rewards him by kicking him in the teeth. Sutton now attempts to cover for him because it's the U.S. Attorney's reputation and credibility that are on the line. Sutton had to save face. It also undermines Aldrete-Davila's credibility and integrity in court.
This kind of thing has happened numerous times throughout history. Prosecutors grant some lowlife immunity from prosecution for a crime. Then the lowlife goes out and commits the crime again. Prosecutors then extend the immunity to cover the subsequent transgression in order justify the mistake of giving him immunity in the first place and to salvage his credibility as a witness.