(concurring in the result):
Appellant’s case was tried in April of 1993. The provision at issue was paragraph 57c(2)(c), Part IV, Manual for Courts-Martial, United States, 1984. It states:
(c) Proof. The falsity of the allegedly perjured statement cannot be proved by circumstantial evidence alone, except with respect to matters which by their nature are not susceptible of direct proof. The falsity of the statement cannot be proved by the testimony of a single witness unless that testimony directly contradicts the statement and is corroborated by other evidence either direct or circumstantial, tending to prove the falsity of the statement. However, documentary evidence directly disproving the truth of the statement charged to have been perjured need not be corroborated if: the document is an official record shown to have [been] well known to the accused at the time the oath was taken; or the documentary evidence originated from the accused — or had in any manner been recognized by the accused as containing the truth — before the allegedly perjured statement was made.
(Emphasis added.) This rule applies to courts-martial for false swearing. See United States v. Tunstall, 24 MJ 235, 237 (CMA 1987), citing para. 213f(4), Manual for Courts-Martial, United States, 1969 (Revised edition), and para. 79c(1), Part IV, 1984 Manual, supra.
Appellant was charged with false swearing, inter alia, by stating: “I have not used narcotics.” The prosecution attempted to prove this offense by introducing a positive urinalysis result for cocaine and expert testimony explaining those results in terms of inferred cocaine use. This was circumstantial evidence of appellant’s drug use offered to prove the falsity of his statement denying drug use. See United States v. Murphy, 23 MJ 310 (CMA 1987); United States v. Harper, 22 MJ 157, 161 (CMA 1986). Thus, appellant at trial and before this Court contends that the so-called two-witness rule of paragraph 57c(2)(e) was violated by the prosecution’s exclusive reliance on circumstantial evidence in this case.
Judge Ripple, writing for the Seventh Circuit, recently explained the so-called two-witness rule in United States v. Chaplin, 25 F.3d 1373,1377 (1994):
Second, at trial, the government must meet, as a general matter, a heightened evidentiary standard for establishing falsity. Under the so-called “two-witness rule,” “the uncorroborated oath of one witness is not sufficient to establish the falsity of the testimony of the accused as set forth in the indictment as perjury.” Hammer v. United States, 271 U.S. 620, 626, 46 S.Ct. 603, 604, 70 L.Ed. 1118 (1926). The two-witness rule “does not literally require the direct testimony of two separate witnesses, but rather may be satisfied by the direct testimony of one witness and sufficient corroborative evidence.” United States v. Diggs, 560 F.2d 266, 269 (7th Cir.), cert, denied, 434 U.S. 925, 98 S.Ct. 404, 54 L.Ed.2d 283 (1977); see also Weiler v. U.S., 323 U.S. 606, 610, 65 S.Ct. 548, 550, 89 L.Ed. 495 (1945). The two-witness rule has two aspects: (1) the falsity of the testimony must be established by more than the uncorroborated oath of one witness and (2) circumstantial evidence, no matter how persuasive, will not by itself support a conviction for perjury. See President’s Commission on Law Enforcement and Administration of Justice, The *308Challenge of Crime in a Free Society 141 (1967).
(Emphasis added.)
The Seventh Circuit in Chaplin held that the two-witness rule did not apply where the alleged false statement concerned a person’s state of mind, i.e., “I do not recall being interviewed by two FBI Agents.” Paragraph 57c(2)(c) more broadly states that its prohibition against use of circumstantial evidence to prove falsity does not apply “with respect to matters which by their nature are not susceptible of direct proof.” See United States v. Guerra, 13 USCMA 463, 32 CMR 463 (1963). Accordingly, the precise question before us is whether cocaine use is a matter which by its nature is susceptible of direct proof. Cf. United States v. Olivero, 39 MJ 246, 251 (CMA 1994) (perjury related to alleged marijuana use).
Obviously, one can readily observe a person snorting a substance up his nose, smoking a substance in a pipe, shooting something into his arm, or swallowing some item. See United States v. Maultasch, 596 F.2d 19, 25 (2d Cir.1979). However, whether that substance is really cocaine or not is usually a matter for identification by science. See United States v. Pabon, 42 MJ 404 (1995); cf. United States v. Tyler, 17 MJ 381 (CMA 1984) (user of drug under certain circumstances can establish identity of drug). Moreover, the secretive nature of drug use has necessitated the practice of proving drug offenses in the military by using urinalysis reports and qualified expert testimony. See United States v. Ford, 4 USCMA 611, 616,16 CMR 185, 190 (1954). Accordingly, I conclude that the two-witness rule, including its prohibition against exclusive reliance on circumstantial evidence, does not apply in this case. Cf. United States v. Olivero, supra (marijuana use susceptible of direct proof).