OPINION ON REHEARING EN BANC
These separate appeals from the District of Utah and the District of Colorado present important questions under the Bail Reform Act of 1984 (“Act”), enacted as part of the Comprehensive Crime Control Act of 1984, Title II of Pub.L. No. 98-473, 98 Stat. 1976, approved October 12, 1984. This court ordered rehearings en banc which were heard on March 12, 1985 in each case. This opinion disposes of the issues in both cases concerning bail pending appeal.
I
Facts
A. Affleck
Defendant Grant C. Affleck was convicted in the District of Utah on October 5, 1984 after a jury trial of six counts of security fraud,1 one count of bankruptcy fraud,2 and one count of interstate transportation of a person to defraud.3 On that date, the district court ordered Affleck re*946leased on a $75,000 bond pending sentencing. The district court found that Affleck did not pose a danger to others or to the community, and that he was not likely to flee.
On November 16, Affleck was sentenced to ten years’ imprisonment and five years’ probation. On November 19, Affleck filed a notice of appeal. On November 20 the district court, in response to Affleck’s ex parte motion, stayed execution of the sentence upon filing of the same bond maintained by Affleck during the trial. The district court found that Affleck posed “no immediate threat of fleeing during appeal and no immediate danger to society during that period.” VIII R. 1438-39.
On November 21, the Government filed a motion in the district court to reconsider its order staying execution of Affleck’s sentence and ordering his release pending appeal, or in the alternative, to hold an expedited hearing and to make the findings to support such an order as required by 18 U.S.C. § 3143(b), as amended by the new Act. Section 203(a) of the Act changed the standards governing release of convicted defendants on bail pending appeal.
Under former 18 U.S.C. §§ 3146 and 3148, convicted defendants were entitled to release on bail pending appeal unless no one or more conditions of release would reasonably assure that they would not flee or pose a danger to any other person or to the community, or unless their appeal was frivolous or taken for purpose of delay. The burden was on the Government under the former law to show that the appeal was frivolous and was taken for purpose of delay; the defendant bore the burden of showing he would not flee and was not a danger to any person or the community. See also former Fed.R.App.P. 9(c). The Act changed the criteria for release on bail pending appeal and placed the burden on the convicted defendant to prove that he meets all the new criteria. Current 18 U.S.C. § 3143(b) provides as follows:
Release or Detention Pending Appeal by the Defendant. — The judicial officer shall order that a person who has been found guilty of an offense and sentenced to a term of imprisonment, and who has filed an appeal or a petition for a writ of certiorari, be detained, unless the judicial officer finds—
(1) by clear and convincing evidence that the person is not likely to flee or pose a danger to the safety of any other person or the community if released pursuant to section 3142(b) or (c); and
(2) that the appeal is not for purpose of delay and raises a substantial question of law or fact likely to result in reversal or an order for a new trial.
Act § 203(a), 98 Stat. 1981-82 (emphasis added); see also Fed.R.App.P. 9(c), as amended by Act § 210, 98 Stat. 1987.
Affleck principally argued below that he was entitled to bail pending appeal because the former law entitled him to that relief, and that application to him of the new Act would violate the ex post facto clause. After a hearing, the district court on December 11 vacated its earlier order. The court held that Affleck had established by clear and convincing evidence under § 3143(b)(1) that he was not likely to flee or pose a danger to the safety of any other person or to the community if he were released on a $75,000 bond pending appeal. The court also held that Affleck had established that his appeal was not taken for purpose of delay under § 3143(b)(2). The court denied bail, however, because Affleck did not establish that his appeal raised a substantial question of law or fact likely to result in reversal or an order for a new trial under § 3143(b)(2). VIII R. 1490. The court also held that application of the new criteria of § 3143(b) to deny Affleck bail pending appeal did not violate the ex post facto clause, even though he would have been entitled to bail under the law in effect when the offenses were committed and when the guilty verdicts were returned. Id. at 1491-95.
B. Kowalik
Defendant Frank Kowalik, Jr. was convicted in the District of Colorado on September 19, 1984 after a jury trial of two *947counts of willfully failing to file federal income tax returns in violation of I.R.C. § 7203. On November 14 the district court sentenced Kowalik to one year of imprisonment and a $10,000 fine on each count. The district court on that date also ordered Kowalik’s release pending appeal upon filing of a $20,000 bond. The court found that Kowalik did not pose a danger to the community and was not likely to flee. I R. 123.
Also on November 14 Kowalik filed a notice of appeal and sought release on the appeal bond, but the magistrate concluded that release was inappropriate absent findings by the district court under § 3143(b). Kowalik principally argued that he was entitled to bail pending appeal under the former law. He also contended that he raised substantial questions likely to result in reversal or an order for a new trial under the new Act. He argued that the trial court erred in its instructions because they did not properly treat his defenses of not willfully and knowingly intending a violation of the tax law, and that the instructions did not properly cover the effect of evidence from his character witnesses. After a hearing on November 15, the district court vacated its earlier order permitting Kowalik to be released on bail pending appeal. The court found that Kowalik had established by clear and convincing evidence under § 3143(b)(2) that he was not a threat to any other person or to the community and was not likely to flee. IX R. 4-5. However, the court held that Kowa-lik’s appeal did not raise a substantial question of law or fact likely to result in reversal or an order for a new trial under § 3143(b)(2), and denied bail. Id. at 3.
C. Proceedings in this court
Both Affleck and Kowalik challenge the district courts’ denial of their motions for release pending appeal. A panel of this court denied the motions for release pending appeal.4 On its own motion this court, by order of a majority of its active circuit judges on February 1, 1985, granted rehearing en banc of of the court’s earlier orders denying the motions for release pending appeal.5 We expedited these cases for argument at our March term of court and asked counsel to brief and argue the effect of the new § 3143(b) standards in these cases. We now address various issues concerning the application to these defendants of the new § 3143(b) criteria for release pending appeal.
II
Effective Date and the Ex Post Facto Clause
A. Effective date
Affleck asserts that Congress did not intend the Bail Reform Act to apply to those convicted of crimes before October 12, 1984. He relies on cases holding that other provisions of the Bail Reform Act do not apply to defendants released on bail before that date. See United States v. Fernandez-Toledo, 749 F.2d 703 (11th Cir. 1985) (§ 3731, which permits the Government to appeal order granting bail); United States v. Mitchell, 600 F.Supp. 164 (N.D.Cal.1985) (§ 3142, which provides for pretrial detention). But see United States v. Anguilo, 755 F.2d 969, 970-74 (1st Cir.1985) (application of pretrial detention provisions of new Act to a defendant incarcerated and seeking release on October 12). Affleck also cites Greene v. United States, 376 U.S. 149, 84 S.Ct. 615, 11 L.Ed.2d 576 (1964), and argues that criminal statutes like § 3143(b) should not be given retrospective operation where to do so would interfere with antecedent rights. See also Fernandez-Toledo, 749 F.2d at 705 (defendant released on bail prior to effective date of the Act had a vested, antecedent right to bail).
*948We are not persuaded by these cases that the Act should not apply to a defendant like Affleck, convicted before October 12, who seeks bail pending appeal after that date. There is no constitutional right to bail pending appeal. See, e.g., United States v. Provenzano, 602 F.Supp. 230, 232 (E.D.La.1985); United States ex rel. Cameron v. New York, 383 F.Supp. 182, 183 (E.D.N.Y.1974).6 In these circumstances, we hold that § 3143(b), in the absence of a showing of congressional intent to the contrary, became fully effective on October 12 when the President approved the Act. Section 3143(b) therefore applies to Affleck even though he was convicted before the effective date of the Act. See United States v. Cirrincione, 600 F.Supp. 1436, 1438 (N.D.Ill.1985); see also United States v. Chiattello, 599 F.Supp. 970, 971-72 (N.D.Ind.1985); United States v. Hazzard, 598 F.Supp. 1442, 1454 n. 8 (N.D.Ill. 1984); United States v. Kowal, 596 F.Supp. 375, 376 (D.Conn.1984); see also United States v. Gavrilovic, 551 F.2d 1099, 1103 (8th Cir.1977); United States v. Clizer, 464 F.2d 121, 123 n. 2 (9th Cir.), cert. denied, 409 U.S. 1080, 93 S.Ct. 679, 34 L.Ed.2d 669 (1972).
B. The ex post facto clause
Affleck and Kowalik both argue that application to them of the new § 3143(b)(2) standards governing bail pending appeal violates the ex post facto clause because they were convicted before the effective date of the Act. We disagree.
The Constitution provides that no “ex post facto [l]aw shall be passed.” U.S. Const, art. I, § 9, cl. 3.7 The ex post facto clauses forbid the enactment by Congress and the states of any law that “imposes a punishment for an act which was not punishable at the time it was committed; or imposes additional punishment to that then prescribed; or changes the rules of evidence by which less or different testimony is sufficient to convict than was then required.” Cummings v. Missouri, 71 U.S. (4 Wall.) 277, 325-26, 18 L.Ed. 356 (1867); see also Weaver v. Graham, 450 U.S. 24, 28, 101 S.Ct. 960, 963, 67 L.Ed.2d 17 (1981).8
The Court has stated that “no ex post facto violation occurs if the change effected is merely procedural, and does ‘not increase the punishment[,] nor change the ingredients of the offen[c]e or the ultimate facts necessary to establish guilt.’ ” Id. at 29 n. 12, 101 S.Ct. at 964 n. 12 (quoting Hopt v. Utah, 110 U.S. 574, 590, 4 S.Ct. 202, 210, 28 L.Ed. 262 (1884) (brackets added to conform to original quotation in Hopt))] see also Dobbert v. Florida, 432 U.S. 282, 293, 97 S.Ct. 2290, 2298, 53 L.Ed.2d 344 (1977) (“Even though it may work to the disadvantage of a defendant, a procedural change is not ex post facto.”)] Beazell v. Ohio, 269 U.S. 167, 171, 46 S.Ct. 68, 69, 70 L.Ed. 216 (1925) (ex post facto clause not intended to “limit the legislative control of remedies and modes of procedure which do not affect matters of substance”). The Court has held that “two critical elements must be present for a *949criminal or penal law to be ex post facto: it must be retrospective, that is, it must apply to events occurring before its enactment, and it must disadvantage the offender affected by it.” Weaver v. Graham, 450 U.S. at 29, 101 S.Ct. at 964 (footnotes omitted).9
We hold that application of the new § 3143(b)(2) standards governing bail pending appeal to a defendant convicted before the effective date of the Act does not disadvantage the defendant in any way prohibited by the ex post facto clause. Section 3143(b)(2) represents a significant procedural change in the requirements that a convicted defendant must meet to obtain bail pending appeal, one seriously disadvantageous to him in that respect, but the statute does not change the “quantum of punishment attached to the crime.” Dobbert, 432 U.S. at 294, 97 S.Ct. at 2298. We agree with other cases, which have similarly held that § 3143(b) does not violate the ex post facto clause. See United States v. Powell, 761 F.2d 1227, 1234 (8th Cir.1985) (en banc) (footnote omitted) (“Admission to bail pending appeal is, for Ex Post Facto Clause purposes, ‘procedural.’ It does not increase the punishment for a crime already committed, but simply regulates the time at which imprisonment for that crime will begin after conviction”); United States v. Molt, 758 F.2d 1198, 1200-01 (7th Cir.1985) (“We think the change in the standard for bail pending appeal is not an ex post facto law---- [T]he presumption is against construing a procedural change as an ex post facto law, and must carry the day in the absence of a stronger showing than made in this case that the change works an increase in punishment---- The change in the balance of advantages against the defendant is too slight to bring the change within the' scope of the ex post facto clause.”); United States v. Miller, 753 F.2d 19, 21 (3d Cir.1985) (“The availability vel non of bail pending appeal, albeit extremely important to the individual involved, is a procedural issue rather than a type of punishment to which the Ex Post Facto Clauses apply.”); United States v. Crabtree, 754 F.2d 1200, 1201-02 (5th Cir.1985) (opinion of Chief Judge Clark as a single circuit judge) (“[ (Section 3143(a)(1) ] is merely procedural and does not alter a substantive right. [It] does not increase the punishment nor change the ingredients of the offense or the ultimate facts necessary to establish guilt.”); United States v. Chiattello, 599 F.Supp. 970, 971 n. 1 (N.D.Ind.1985) (“The method governing the release of a defendant on appeal following a conviction is a matter of procedure and does not bear on substantive rights.”); United States v. Davis, 598 F.Supp. 453, 468 (S.D.N.Y.1984) (on motion to revoke bail) (“[Defendant’s] entitlement to bail, and the criteria by which that entitlement will be measured, constitute ‘modes of procedure’ falling outside the ex post facto rule, notwithstanding the fact that increased restrictions upon bail pending appeal may undoubtedly ‘work to the disadvantage’ of defendants.”).
In reaching this conclusion, we are mindful of the Supreme Court’s decision in Kring v. Missouri, 107 U.S. 221, 2 S.Ct. 443, 27 L.Ed. 506 (1883). In Kring, the Court held that an ex post facto violation had occurred where the Missouri courts had imposed a death penalty by a second sentence in a murder case. A former plea of guilty to a second degree murder charge had resulted in a twenty-five year sentence; the defendant appealed and the judgment was reversed. Under Missouri law in force when the homicide was committed, the first sentence constituted an acquittal of first degree murder. Before retrial, the state law was changed so that this effect of an acquittal of first degree murder no longer operated. The defendant refused to withdraw his plea of guilty to second degree murder or to reenter a not guilty plea to the first degree murder charge. The trial court ordered a general not guilty plea entered to the first degree murder charge. The retrial, guilty verdict and death sentence followed, which the Missouri courts *950affirmed. The Supreme Court reversed. The Court upheld the ex post facto claim and rejected the contention that the change in state law was merely a change in criminal procedure. Id. at 232-36, 2 S.Ct. at 452-55. The troublesome discussion is as follows:
But it cannot be sustained without destroying the value of the constitutional provision, that a law, however it may invade or modify the rights of a party charged with crime, is not an ex post facto law, if it comes within either of these comprehensive branches of the law designated as Pleadings, Practice, and Evidence.
Can the law with regard to bail, to indictments, to grand jury, to the trial jury, all be changed to the disadvantage of the prisoner by State legislation after the offence was committed, and such legislation not held to be ex post facto legislation, because it relates to procedure, as it does according to [Bishop on Criminal Procedure ]?
And can any substantial right which the law gave the defendant at the time to which his guilt relates be taken away from him by ex post facto legislation, because, in the use of a modern phrase, it is called a law of procedure? We think it cannot.
Id. at 232, 2 S.Ct. at 452 (emphasis added).
We believe that Kring and its dictum respecting bail must be read in light of later Supreme Court opinions on the ex post facto clause. In Beazell, for example, the Court stated that “[ejxpressions are to be found in earlier judicial opinions to the effect that the [ex post facto clause] may be transgressed by alterations in the rules of evidence or procedure.” 269 U.S. at 170, 46 S.Ct. at 68 (citing Kring, inter alia). The Court conceded that there “may be procedural changes which operate to deny to the accused a defense available at the time of the commission of his offense, or which otherwise affect him in such a harsh and arbitrary manner as to fall within the constitutional prohibition.” Id. The Court noted that “[j]ust what alterations of procedure will be held to be of sufficient moment to transgress the constitutional prohibition cannot be embraced within a formula or stated in a general proposition. The distinction is one of degree. But the constitutional provision was intended to secure substantial rights against arbitrary and oppressive legislation.” 269 U.S. at 171, 46 S.Ct. at 69.
In Kring, the Court explained that the effect of the change in state law, which was denied application there as ex post facto, was that formerly conclusive evidence of innocence of the higher grade of murder could not be received at all, or was given no weight, and that the law on punishment was changed from a bar against the death penalty in such circumstances to a new law permitting such punishment. 107 U.S. at 228, 2 S.Ct. at 449. Although we are bound by that holding in Kring, we must view the statements concerning bail and procedural changes in Kring in light of the ex post facto standards applied by the Court in subsequent cases. We are particularly persuaded by the Court’s more recent focus in ex post facto cases on the elements of the offense, the conditions and quantum of punishment, and the quantity and degree of proof necessary to establish guilt. See, e.g., Weaver v. Graham, 450 U.S. at 32-33, 101 S.Ct. at 966-967; Dob-bert, 432 U.S. at 295, 97 S.Ct. at 2299. In light of these standards, we conclude that there is no ex post facto violation here by application of the new restrictive rules governing bail pending appeal, as now prescribed by § 3143(b)(2).
We are unpersuaded by the reasoning in United States v. Cirrincione, 600 F.Supp. 1436 (N.D.Ill.1985). There the district court held that § 3143(b)(2) violates the ex post facto clause. The court reasoned that a sentence which begins immediately is more severe than a sentence which commences after an unsuccessful appeal. Id. at 1443-46. The court said that “[w]hile the Supreme Court has not always been clear on the underlying rationales for the ex post facto clause, certainly one rationale is that an individual who acts in reliance upon the known criminal penalties for his acts must be punished in accordance with that reliance.” Id. at 1444.
*951Although we agree that the ex post facto clauses protect an individual who acts in reliance on the known criminal penalties for his conduct, we cannot accept the Cir-rincione court’s view that § 3143(b)(2) affects the punishment imposed for such conduct. A convicted defendant may wish to postpone serving his sentence until his appeal is decided, and certainly the § 3143(b)(2) standards for granting bail pending appeal are “more onerous” than those under the former law. However, § 3143(b)(2) does not in any way alter the “quantum of punishment” imposed on criminal defendants, or the elements and required proof of the offense, which are the main focus of the Supreme Court’s more recent decisions. Dobbert illustrates the fact that significant changes, even in the procedure for imposition of the death penalty, do not necessarily violate the ex post facto clause.
Our conclusion is also supported by state court decisions which have upheld changes in statutes governing bail pending appeal against ex post facto challenges. For example, the Indiana Supreme Court has held that a state statute denying bail pending appeal by a habitual criminal was not ex post facto as applied to a defendant who committed the offense and was convicted before the effective date of the statute. State ex rel. Dorton v. Circuit Court of Elkhart County, 274 Ind. 373, 412 N.E.2d 72 (1980).10 The court explained that the superseding statute did “not make an act criminal which was legal before the statute; nor [did] it ‘provide a greater punishment therefor than was prescribed at the time of its commission.’ ” Id. at 74 (quoting Hopt v. Utah, 110 U.S. 574, 579, 4 S.Ct. 202, 204, 28 L.Ed. 262 (1884)).
Moreover, the Oklahoma Court of Criminal Appeals has held that a state statute prohibiting bail pending appeal if a defendant was convicted of rape or forcible sodomy, among other things, was not ex post facto as applied to a defendant who committed the offense before the effective date of the statute. Spitznas v. State, 648 P.2d 1271 (Okla.Crim.App.1982). The court concluded that the statute was procedural and did not inflict greater punishment than the law imposed at the time the offense was committed. Id. at 1275-76.
In addition, the District of Columbia Court of Appeals has held that a statute providing for pretrial detention of defendants charged with first degree murder was not ex post facto as applied to a defendant who committed the crime before the effective date of the statute. De Veau v. United States, 454 A.2d 1308 (D.C.App.1982), cert. denied, 460 U.S. 1087, 103 S.Ct. 1781, 76 L.Ed.2d 351 (1983). The court emphasized that the statute did not “impose (or increase) punishment... or [make] formerly legal conduct a crime.” Id. at 1314.11
We therefore hold that the § 3143(b)(2) standards governing bail pending appeal are not ex post facto as applied to a defendant where the offenses charged and the resulting convictions occurred before the effective date of the Act, but the sentences and the order by the district court denying bail pending appeal were entered after that date.
*952III
Interpretation of 18 U.S.C. § 3143(b)(2)
Section 3143(b)(2) as amended by the Bail Reform Act requires that bail pending appeal be denied unless the court finds that the appeal “raises a substantial question of law or fact likely to result in reversal or an order for a new trial.” The parties in both the Affleck and Kowalik cases contend that we should interpret this requirement in light of the two-step analysis announced by the Third Circuit in United States v. Miller, 753 F.2d 19 (3d Cir. 1985). The Government, however, argues that a stricter interpretation than that of Miller should be applied to determine what constitutes a “substantial” question of law or fact.
In Miller, the Third Circuit held that the language quoted above requires the court to make two determinations in order to grant bail pending appeal. First, the court must decide that the appeal raises a “substantial” question of law or fact. Second, “if that substantial question is determined favorably to defendant on appeal, that decision is likely to result in reversal or an order for a new trial of all counts on which imprisonment has been imposed.” Id. at 24. This approach has been followed in other cases. See United States v. Powell, 761 F.2d 1227, 1230-1234 (8th Cir.1985) (en banc); United States v. Handy, 761 F.2d 1279, 1280 (9th Cir.1985) (per curiam); United States v. Giancola, 754 F.2d 898, 900-901 (11th Cir.1985); see also United States v. Polin, Nos. 85-5009, 85-5010, slip op. at 2 (4th Cir. March 4, 1985) (opinion of Murnaghan, Circuit Judge, as a single circuit judge). We adopt the Miller two-step analysis for determining whether to grant bail pending appeal under § 3143(b), but we apply a somewhat stricter interpretation of what constitutes a “substantial” question of law or fact, which we believe the statute and its purpose require.
What constitutes a “substantial” question under the first prong of this test must be considered in light of congressional intent. Under former § 3148, bail pending appeal would be denied if the appeal was “frivolous.” The new Act was intended to reverse the presumption in favor of bail pending appeal under the former law and to make the standards for granting bail pending appeal more stringent. See S.Rep.No. 225, 98th Cong., 1st Sess. 26-27, reprinted in 1984 U.S.Code Cong. & Ad. News 3182.
Accordingly, we agree with the Eleventh Circuit that “a ‘substantial question’ is one of more substance than would be necessary to a finding that it was not frivolous. It is a ‘close’ question or one that very well could be decided the other way.” Giancola, 754 F.2d at 901. In Miller, the Third Circuit said that a “substantial” question under § 3143(b)(2) “is one which is either novel, which has not been decided by controlling precedent, or which is fairly doubtful.” Miller, 753 F.2d at 23.12 We agree with the Eleventh Circuit, however, that a question “which has not been decided by controlling precedent” may not be “substantial” under § 3143(b)(2). For example, an issue may be “so patently without merit that it has not been found necessary for it to have been resolved____ Similarly, there might be no precedent in this circuit, but there may also be no real reason to believe that this circuit would depart from unanimous resolution of the issue by other circuits.” Giancola, 754 F.2d at 901.13 In the final analysis, we cannot define blanket categories for what will constitute “substantial” questions under § 3143(b)(2). Therefore, whether a particular question is “substantial” must be determined on a case-by-case basis, under the general guidelines we adopt as quoted above. See Giancola, 754 F.2d at 901.
The second prong of the Miller test poses less of a definitional problem. Under this second prong, bail pending appeal is *953appropriate if, assuming that the “substantial question is determined favorably to defendant on appeal, that decision is likely to result in reversal or an order for a new trial of all counts on which imprisonment has been imposed.” Miller, 753 F.2d at 24. The Third Circuit further explained that this language
must be read as going to the significance of the substantial issue to the ultimate disposition of the appeal. A question of law or fact may be substantial but may, nonetheless, in the circumstances of a particular case, be considered harmless, to have no prejudicial effect, or to have been insufficiently preserved. A court may find that reversal or a new trial is “likely” only if it concludes that the question is so integral to the merits of the conviction on which defendant is to be imprisoned that a contrary appellate holding is likely to require reversal of the conviction or a new trial.
Id. at 23.14
In sum, we hold that in order to grant bail pending appeal, a court must find that the defendant has met his burden of proving by clear and convincing evidence that he is not likely to flee or pose a danger to the safety of any other person or to the community if released under § 3143(b)(1), and that he has established under § 3143(b)(2)15 that the appeal is not for purpose of delay, and:
[1.] that the appeal raises a substantial question of law or fact; and
[2.] that if that substantial question is determined favorably to defendant on appeal, that decision is likely to result in reversal or an order for a new trial of all counts on which imprisonment has been imposed.
Id. at 24.
IV
Disposition
In Affleck, both the defendant and the Government agree that we should remand the case to the district court to reconsider the issue of bail pending appeal under the Miller two-part standard, disagreeing only on how to determine a “substantial” question of law or fact, which we have resolved. In Kowalik, however, both the defendant and the Government apparently agree that a remand is not appropriate. Kowalik argues that we should grant him bail pending appeal under the test he espouses, while the Government argues that we should deny bail under the standard it proposes.
We conclude that the proper disposition is to remand both cases for the district court to make findings and conclusions under the standard for determining bail on appeal which we adopt today. The Third and Eleventh Circuits made this disposition in Miller and Giancola. Miller, 753 F.2d *954at 24; Giancola, 754 F.2d at 901 & n. 5.16 This disposition comports with Fed.R. App.P. 9(b). Rule 9(b) requires that applications for bail pending appeal be made “in the first instance in the district court.” Id. The rule also requires the district court to “state in writing the reasons” if the court denies release pending appeal or imposes conditions on release. Id. The rule contemplates that the district court is in a better position to evaluate, in the first instance, the propriety of granting bail pending appeal. The rule also aids our appellate function by requiring the district court to make written findings and conclusions.
These proceedings obviously present difficulties for the parties, as well as for the trial and appellate courts. We are convinced that those difficulties will be lessened if a clear record at a hearing is made in the trial court. As noted, the defendant bears the burden of making the showings outlined above on the facts and the law, and he must present sufficient portions of the record to support the questions he raises. If this is not done, as to evidentiary matters we must give considerable deference to the trial court’s determination on the substantiality of questions of fact. We can, like the trial court, independently consider questions of law.
Accordingly, we partially remand these cases to the district courts for hearings and reconsideration of the denials of the motions for bail pending appeal under the standards we adopt today, and for the district courts to make new written findings, conclusions and orders under these standards. This court otherwise retains jurisdiction of the principal appeals in these cases. The mandates for the partial remands shall issue forthwith.
. 15 U.S.C. § 78j; 17 C.F.R. § 240-10b-5.
. 18 U.S.C. §§ 152, 2.
. 18 U.S.C. § 2314.
. Kowalik’s petition for a stay pending appeal was denied by order of a panel of this court on December 4, 1984. Affleck’s motion for release pending appeal was denied by order of a panel of this court on December 27, 1984.
. Chief Judge Holloway and Judge Barrett voted to deny rehearing en banc.
. The legislative history of the Bail Reform Act notes that "there is clearly no constitutional right to bail once a person has been convicted.” S.Rep. No. 98-225, 98th Cong., 2d Sess. 26, reprinted in 1984 U.S.Code Cong. & Ad.News 3182, 3209 (footnote omitted).
. The Constitution also prohibits the states from passing ex post facto laws. U.S. Const, art. I, § 10, cl. 1 (“No State shall ... pass any ... ex post facto [l]aw____”).
. The Court has emphasized that “[t]he mark of an ex post facto law is the imposition of what can fairly be designated punishment for past acts.” De Veau v. Braisted, 363 U.S. 144, 160, 80 S.Ct. 1146, 1154, 4 L.Ed.2d 1109 (1960) (plurality opinion) (emphasis added). See also Beazell v. Ohio, 269 U.S. 167, 169-70, 46 S.Ct. 68, 68-69, 70 L.Ed. 216 (1925) (“[A]ny statute which punishes as a crime an act previously committed, which was innocent when done; which makes more burdensome the punishment for a crime, after its commission, or which deprives one charged with crime of any defense available according to law at the time when the act was committed, is prohibited as ex post facto.")', Paschal v. Wainwright, 738 F.2d 1173, 1176 n. 4 (11th Cir.1984) (emphasis in original) (For ex post facto violation to have occurred, “the legislature must provide punishment for past conduct.”).
. See also Paschal v. Wainwright, 738 F.2d 1173, 1175-76 (11th Cir.1984); Artez v. Mulcrone, 673 F.2d 1169, 1171 (10th Cir.1982); see generally J. Nowak, R. Rotunda & J. Young, Constitutional Law 477-78 (2d ed. 1983); L. Tribe American Constitutional Law 477-84 (1978).
. The court explained that “[t]he necessity to protect society against further criminal acts by a convicted, but unpunished, person [by denying bail pending appeal] outweighs society’s interest in protecting persons who may have a reversible conviction.” 412 N.E.2d at 74.
. But see Greene v. State, 238 So.2d 296, 300-01 (Fla.1970) (application of bail statute to deny bail pending appeal from conviction on second felony violated ex post facto clauses where bail statute became effective after commission of second felony); Cunningham v. State, 423 So.2d 580 (Fla.Dist.Ct.App.1982) (per curiam) (ex post facto clause prohibited application of statute denying bail pending appeal of drug trafficking conviction to defendant who committed offense before effective date of statute); cf. Parker v. State, 667 P.2d 1272 (Alaska Ct.App.1983) (right to bail pending appeal sufficiently accrued at time of offense under state statute so that statute passed after date of offense but before conviction which eliminated bail for persons convicted of certain felonies did not apply to defendant); Ellis v. State, 544 S.W.2d 908, 911 (Tenn.Crim.App.1976) (statute denying bail pending appeal to defendants convicted of possession of controlled substances with intent to sell had "ex post facto overtones” when applied to defendants who were arrested after effective date of statute).
. See also Handy, 761 F.2d at 1281 ("substantial” question is one that is "fairly debatable").
. Of course, a "substantial" question must be one which can be properly raised on appeal. See Gianola, 754 F.2d at 901 n. 4.
. The Third Circuit rejected the view that § 3143(b)(2) requires the district court to grant bail pending appeal only upon finding that its own rulings were likely to be reversed on appeal for two reasons:
In the first place, such a reading would render language in the statute surplusage because every question that is likely to be reversed must by definition be "substantial”. In the second place, we are unwilling to attribute to Congress the cynicism that would underlie the provision were it to be read as requiring the district court to determine the likelihood of its own error. A district judge who, on reflection, concludes that s/he erred may rectify that error when ruling on post-trial motions. Judges do not knowingly leave substantial errors uncorrected, or deliberately misconstrue applicable precedent. Thus, it would have been capricious of Congress to have conditioned bail only on the willingness of a trial judge to certify his or her own error.
For a similar reason, the phrase “likely to result in reversal or an order for a new trial" cannot reasonably be construed to require the district court to predict the probability of reversal. The federal courts are not to be put in the position of “bookmakers” who trade on the probability of ultimate outcome.
Miller, 753 F.2d at 23; see also Polin, slip op. at 2 n. 2; Handy, 761 F.2d at 1280; Giancola, 754 F.2d at 900.
. We note that, unlike § 3143(b)(1), § 3143(b)(2) does not require that the showing be made by "clear and convincing evidence.” We therefore conclude that a defendant must only prove the § 3143(b)(2) criteria under the ordinary preponderance of the evidence standard.
. In Polin, a single judge of the Fourth Circuit adopted the Miller standard and agreed with the district court’s denial of bail pending appeal because the defendant did not meet his burden of showing that his appeal raised a "substantial" question. Polin, slip op. at 3-4.
In Handy, the Ninth Circuit adopted the Miller standard and disagreed with the district court’s denial of bail pending appeal. The Ninth Circuit granted bail pending appeal and held that the defendant had met his burden of proving that his appeal raised a “substantial or ‘fairly debatable’ question of the type that calls into question the validity of the judgment.” Handy, 761 F.2d at 1283. The Ninth Circuit remanded to the district court for imposition of the appropriate conditions of release.