Except when time is an essential element of the offense, the time allegation is not material to the sufficiency of the indictment if the error or variance in proof is within reasonable limits. Time was material to an indictment charging a willful failure to file an income tax return by the April 15 deadline. Therefore, evidence showing that the defendant had obtained a filing extension until May 7 of that year caused a fatal variance. See United States v. Bowman, 783 F.2d 1192 (5th Cir. 1986); United States v. Cochran, 697 F.2d 600 (5th Cir. 1983); United States v. Goldstein, 502 F.2d 526 (3d Cir. 1974). ("[V]ariance between dates alleged and dates proven will not trigger reversal. . . as long as the date proved falls within the statute of limitations and before the return date of the indictment." United States v. Alexander, 850 F.2d 1500, 1504 (11th Cir. 1988), quoting, United States v. Harrell, 737 F.2d 971, 981 (11th Cir. 1984), cert. denied, 469 U.S. 1164 (1985) (omission in original). See also Russell v. United States, 429 F.2d 237 (5th Cir. 1970).
Courts have allowed considerable leeway as to the specificity of the alleged date of an offense in an indictment. Using the phrase "on or about" is proper. United States v. Giles, 756 F.2d 1085 (5th Cir. 1985). Citing hornbook law that great generality is allowed as to the alleged date of an offense in an indictment, it was held that a count charging that an alien smuggling offense took place "on or about 1977, the exact date to the grand jury unknown" was within reasonable limits. See United States v. Nunez, 668 F.2d 10, 11 (1st Cir. 1981).
One court has reasoned that the more specific the time allegation, the stronger is the inference that the grand jury was only indicting a defendant for acts occurring on the specific dates charged, whereas use of the qualifying phrase, "on or about" indicated a grand jury unwillingness to pinpoint the date of the offense charged. See United States v. Somers, 496 F.2d 723, 745 (3d Cir), cert. denied, 419 U.S. 832 (1974). Thus, a fatal variance was held to have occurred when an indictment charged that the subject extortionate acts occurred "on October 7 and October 8, 1962," but the proof showed such acts occurred on August 10 and October 5, 1962. See United States v. Critchley, 353 F.2d 358 (3d Cir. 1965). In contrast, the court in United States v. Grapp, 653 F.2d 189 (5th Cir. 1981), readily rejected a variance claim when the proof at trial showed that the time of the offense was the middle of 1977 and the indictment charged it had occurred "on or about May 27, 1977."