Defendant David Glen Ussery was charged with possession of ethel ether and acetic anhydride knowing it to be used to manufacture a controlled substance, in violation of 21 U.S.C. § 841(d)(2), and aiding and abetting, in violation of 18 U.S.C. § 2. The district court found that there was probable cause to search the car in which defendant was a passenger at the time he was arrested, and it denied his motion to suppress as evidence the chemicals found in the car. Defendant entered a conditional guilty plea pending appeal of this ruling. We affirm.1

"When reviewing a district court's denial of a motion to suppress, we accept the district court's factual findings unless they are clearly erroneous. The ultimate determination of reasonableness under the fourth amendment is a question of law, which we review de novo." United States v. Arango, 912 F.2d 441, 444 (10th Cir.1990) (citations omitted), cert. denied, 111 S. Ct. 1318 (1991).

Responding to a tip from a confidential informant, a special agent of the federal Drug Enforcement Agency (DEA) set up surveillance at a retail chemical business in Albuquerque, New Mexico. The informant had stated that an individual, bearing a certain general description and driving a maroon or burgundy Oldsmobile bearing Texas license plates with a certain number, intended to purchase acetic anhydride, methanol, ethel ether, and some glassware at the store. The special agent and the informant discussed the probability that the chemicals were being purchased to manufacture a controlled substance. The agent determined that the car was registered to a woman from Lake Jackson, Texas, 800 miles from Albuquerque, and he then set up surveillance at the chemical business named by the informant. The described car arrived at the store shortly thereafter, and the male driver, who met the general description given in the tip, was observed going into the business, then driving around to the back of the building and loading several white five-gallon containers into the trunk. The agent followed the car, which proceeded to a motel where it was parked in the shade at one side of the motel. Defendant and another individual brought various items to the car from a room on the other side of the motel and packed the car. The two men then drove the car to an east-bound interstate highway and were headed out of the area on the interstate when the special agent requested that local police stop the car. They did so, and when the special agent arrived, he informed defendant and the other occupant of the car that an investigation was being conducted into the purchase of chemicals to be utilized in the illicit manufacture of drugs. The special agent searched the car without warrant or consent and found the chemicals named in the indictment.2 Defendant and his companion were arrested.

Defendant moved that evidence of the chemicals' presence in the car be suppressed because he claimed that the government did not have probable cause to search the car, given the information the special agent had prior to the search.3

[P]robable cause is a flexible, common-sense standard. It merely requires that the facts available to the officer would "warrant a man of reasonable caution in the belief," that certain items may be ... useful as evidence of a crime; it does not demand any showing that such a belief be correct or more likely true than false.

A "practical, nontechnical" probability that incriminating evidence is involved is all that is required....

"... Long before the law of probabilities was articulated as such, practical people formulated certain common-sense conclusions about human behavior; jurors as fact-finders are permitted to do the same--and so are law enforcement officers."

Texas v. Brown, 460 U.S. 730, 742 (1983) (citations omitted); accord United States v. Padilla, 819 F.2d 952, 962 (10th Cir.1987).

At the suppression hearing, defendant submitted the offer of proof of an expert witness, a chemist. The expert testified that the chemicals seized from the car had so many common uses that presumption of their use for the production of controlled substances was unwarranted. The court ruled that what the expert witness knew and testified about the chemicals was irrelevant. It ruled that the test for probable cause to search was determined by what the special agent knew and observed about defendant, defendant's conduct, and the chemicals at the time of the search. The district court was correct; probable cause is measured from the perspective of the trained law enforcement officer. See Texas v. Brown, 460 U.S. at 742.

The special agent testified in detail about the conclusions he reached based on the facts given to him by the confidential informant and the conduct he observed.4 The district court ruled that this testimony was sufficient to support probable cause for the search. To the extent that this conclusion was based on factual findings that the defendant's conduct raised the agent's suspicions to the level necessary to support probable cause, these findings were not clearly erroneous. And, as a matter of law, the tip given to the special agent by the confidential informant, combined with the observations made by the special agent prior to defendant's arrest, provided sufficient basis for probable cause for the search here in question.

The judgment of the United States District Court for the District of New Mexico is AFFIRMED.