mentary, application note 4. The Commission thus sought to avoid double-counting conduct obstructive of judicial proceedings in applying the obstruction adjustment.
The majority notes that section 3C1.1, interpreted broadly, encompasses wholly ineffectual attempts to obstruct justice. This expansive reading, however, conflicts with the basic tenet of statutory interpretation requiring courts to construe penal statutes narrowly. See Dowling v. United States, 473 U.S. 207, 215-16, 105 S.Ct. 3127, 3132, 87 L.Ed.2d 152, 159 (1985); Williams v. United States, 458 U.S. 279, 290, 102 S.Ct. 3088, 3094, 73 L.Ed.2d 767 (1982). Additionally, the majority’s reasoning ignores the principle of proportionality and section 3Cl.l’s necessary concern with the potential for harm created by a defendant’s obstruction of justice. See generally U.S.S.G. ch. 1, pt. A, policy statement (The Basic Approach); cf. United States v. Baker, 894 F.2d 1083, 1084 (9th Cir.1990) (defendant’s lies to probation officer had potential for obstructing justice and were therefore material under section 3C1.1 although court eventually discovered true extent of defendant’s criminal record). The majority treats Blackman in the same manner as it would a defendant who threatens injury to a witness. This result is contrary to the purposes of the guidelines and lacks penological justification.
The majority approves an increase in Blackman’s offense level equivalent to those received in United States v. Patterson, 890 F.2d 69 (8th Cir.1989), and United States v. Brett, 872 F.2d 1365 (8th Cir.1989). In Patterson and Brett, the defendants’ obstructive efforts had both greater potential for harm to the administration of justice and greater actual obstructive effect than did Blackman’s. I would have dissented from the results in Patterson and Brett had I been on those panels, because I believe that the conduct of the defendants in those cases, albeit more egregious than Blackman’s, did not merit a possible increase in their sentences of twenty-five percent. A comparison of the facts of those cases with Blackman’s conduct nonetheless illustrates the disparity in sentencing that the majority’s holding promotes.
In Patterson, the defendant gave a false name on arrest and at a post-arrest FBI interview. 890 F.2d at 70-71. He also gave the FBI agent a false date and place of birth and refused to give his name to the magistrate. Id. at 71. The FBI had to obtain the defendant’s motel phone records and perform a fingerprint comparison before confirming the defendant’s actual identity. Id. In Brett, the defendant gave a false name on arrest and did not admit his true identity to authorities until twenty-six days later. 872 F.2d at 1368. The district court found that Brett’s delay in correctly identifying himself cost the government time, manpower, and money. Id. at 1372-73. Thus, each of these defendants’ use of a false name, unlike Black-man’s, had some potential to actually hinder the administration of justice.
The obstruction adjustment to Black-man’s offense level increased his sentencing range from 235-293 months to 292-365 months. In Brett and Patterson, the defendants’ sentencing ranges increased from 97-121 months to 121-151 months and from 46-57 months to 57-71 months, respectively. Blackman’s futile attempt to conceal his identity thus earned him a twenty-four percent increase in his sentencing range, while the defendants in Brett and Patterson received twenty-three and twenty-five percent increases. Because of Blackman’s higher base offense level, his increase amounts to substantially more real time than was received in Brett and Patterson, cases in which the defendants’ attempted obstruction actually hindered their prosecution.
Although such disparities are to some extent inevitable under the guidelines, extending section 3C1.1 to conduct as innocuous as Blackman’s futile attempt to avoid apprehension increases the risk that the obstruction adjustment will be used to punish widely varying levels of evasive conduct with sentences of undifferentiated severity. Moreover, by applying section 3C1.1 to conduct engaged in during the commission of a crime to avoid apprehension, the majority creates the possibility that any affirmative step taken by a defendant to avoid detection could qualify for a two-level increase for obstruction of justice. Thus, conduct such as concealing one’s identity from