Former San Diego-area Border Patrol agent pleads guilty to drug charge in federal court


A former Border Patrol agent pleaded guilty this week in San Diego federal court to a conspiracy charge stemming from his role in a drug-trafficking ring.

Cesar Daleo, 47, pleaded guilty Thursday to one count of conspiracy to distribute controlled substances, according to the U.S. attorney’s office. He’s scheduled to be sentenced in September by U.S. District Judge Gonzalo Curiel.

The conspiracy charge carries a maximum penalty of 20 years in prison and a $500,000 fine. A plea agreement in the case remained sealed.


Daleo was arrested in San Diego County last August while headed to Tijuana, federal prosecutors said. He was carrying a package sent from China that he’d just picked up at a San Ysidro post office box, believing it contained 4ANPP, a chemical precursor to fentanyl, an opioid that is used as a pain medication.

Daleo, who was indicted in April on federal charges of smuggling protected sea cucumbers and sea horses, worked as a Border Patrol agent in the San Diego area from 1992 to 2003. A resident of San Ysidro, Daleo was living in a condo on the Mexican side of the border at the time of his arrest, prosecutors said.

According to federal prosecutors, Daleo picked up at least 13 packages at the San Ysidro post office box before he was arrested Aug. 29 while heading south on Interstate 5 toward Tijuana. But the package he had that day was not actually the fentanyl precursor — federal agents had already replaced the chemical with a harmless substitute.

On Aug. 11, a U.S. Customs and Border Protection agent at Los Angeles International Airport discovered that a package sent from China and bound for San Ysidro contained 1 kilogram of 4ANPP, which is enough to make 25 kilograms of fentanyl, authorities said. The chemical was hidden inside a package labeled lotus root starch, prosecutors said.

Weeks later, with the substitute substance in place, the package was forwarded to San Ysidro, where Drug Enforcement Administration and other federal agents waited to see who would pick up the shipment. Though the post office box was registered to another man, it was Daleo who picked up the package and signed for it, prosecutors said.

Records showed it was the 14th time since December 2016 that Daleo had signed for a package delivered to the post office box, and no one else had done so in that time, authorities said.


The federal agents followed Daleo until he drove onto a freeway lane that led only to Mexico. That’s where they stopped and arrested him.

Federal officials say trafficking rings like the one Daleo was a part of have created what is essentially a fentanyl pipeline from China to the U.S. that’s connected by an online marketplace on the dark web, where drug purchases can be made with anonymity.

The nature of fentanyl — extremely potent in small doses when pure — makes it ideal to move through the mail, keeping packages small and inconspicuous.

The pipeline also brings the cheap 4ANPP from China to the U.S., then south of the border to Mexican cartel strongholds, where it is cut with other substances. The drugs then head north on well-established trafficking routes for sale to customers in the U.S.