On September 29, 1960, petitioner-appellant was convicted of three offenses: two counts charging transportation in interstate commerce of falsely made securities, Title 18 U.S.C. Section 2314, and one count under Title 18 U.S.C. Section 371 of conspiracy to violate Section 2314. He was sentenced to two consecutive ten-year terms of imprisonment for *1130the substantive charges, and a concurrent five-year term under the conspiracy count.
Immediately after sentence was imposed November 9, 1960, petitioner-appellant signed an election not to commence service of the sentence pending appeal pursuant to the provisions of F. R.Crim.P. 38(a)(2) then in effect.1 That election stated:
“I understand that as a result of making this election I will not receive credit on my sentence for time spent in jail . . . awaiting the outcome of my appeal.”
Because he failed to meet the requirements for bail, petitioner-appellant remained in the county jail until his conviction was affirmed by this Court on August 16, 1961, and his motion for rehearing was denied on September 14, 1961. Popeko v. United States, 5 Cir. 1961, 294 F.2d 168. Shortly thereafter he was moved to a federal prison and commenced serving his sentence.
Petitioner-appellant moved in the district court for his sentence to be corrected so that he will receive credit for the period of time spent in the county jail pending the final adjudication of his appeal, asserted to be 354 days. Notwithstanding the signed election his motion asserted that he did not sign the Rule 38(a)(2) waiver voluntarily or with a full understanding of its consequences. Therefore he contends, it should be of no binding effect. The district court denied relief, without a hearing, relying on Shelton v. United States,2 5 Cir. 1956, 234 F.2d 132, where we held:
“After his motion for new trial was denied, he gave notice of appeal and then elected not to serve his sentence. Having thus voluntarily elected not to serve, service of his sentence automatically ceased, . . . (citations omitted) . . . and he may not now complain of the results of his voluntary action.” 234 F.2d at 133-134.
Before deciding whether petitioner-appellant is entitled to credit for the time he served in jail pending his appeal, it is necessary to answer a more basic inquiry. The key question is the truth or falsity of the assertion that his execution of the Rule 38(a)(2) election was neither voluntary nor entered into with a full understanding of its consequences. Davis v. United States, 7 Cir. 1971, 446 F.2d 847, 849; Johnson v. United States, 9 Cir. 1969, 414 F.2d 807; Bujese v. United States, 3 Cir. 1968, 404 F.2d 615; and Cephus v. United States, 1967, 128 U.S.App.D.C. 366, 389 F.2d 317. Indeed, the Shelton court assumed this premise in answering the question of credit for time served in jail pending appeal. We repeat for emphasis a portion of our quotation from Shelton, supra:
“Having thus voluntarily elected not to serve, service of his sentence automatically ceased . . . (citations omitted) . . . and he may not now complain of the results of his voluntary action.” (Emphasis added)
Because findings of fact as to Popeko’s allegation that his election was neither voluntarily nor knowingly executed are absent, we reverse and remand for an evidentiary hearing below so that such findings may be made.
Reversed and remanded.