State v. Harris, 2013 Mo. LEXIS 254

In 2011 Harris was arrested for knowingly possessing a .38 revolver in violation of Mo. Rev. Stat. § 571.070.
Harris previously pleaded guilty in 2001 to possession of a controlled substance with intent to distribute (a felony that was not a statutory “dangerous felony”).
Prior to a 2008 amendment, § 571.070 prohibited only previously convicted "dangerous felons" from possessing a concealable firearm; the 2008 amendment expanded the ban to all felons.
Harris moved to quash the indictment, arguing the 2008 amendment, as applied to his pre-2008 conviction, violated Article I, § 13 (ex post facto) of the Missouri Constitution; the circuit court granted the motion and dismissed with prejudice.
The State appealed; the Missouri Supreme Court reviewed de novo and transferred the case to the Court en banc because it involves the validity of a statute.
The Supreme Court reversed the circuit court, holding § 571.070 is not an ex post facto law as applied to Harris and remanded the case.

Issue	Plaintiff's Argument	Defendant's Argument	Held
Whether § 571.070 (as amended in 2008) is an ex post facto law as applied to Harris	Harris: applying the 2008 amendment to his 2001 conviction retroactively makes his earlier offense more burdensome and thus is ex post facto	State: § 571.070 punishes post-enactment possession; it uses the prior conviction only as an antecedent fact and does not punish past conduct	Held: Not ex post facto — the statute punishes new possession occurring after amendment, not the prior conviction
Whether § 571.070 increases punishment for Harris’s past crime	Harris: the amendment effectively increases burdens tied to his 2001 conviction	State: the statute does not alter punishment for the 2001 offense; it imposes punishment for a later act (possession)	Held: No increase of punishment for the prior crime; statute targets later conduct

State v. Mixon, 391 S.W.3d 881 (Mo. banc 2012) (standard for reviewing constitutional challenges to statutes)
Doe v. Phillips, 194 S.W.3d 833 (Mo. banc 2006) (Missouri’s ex post facto ban construed coextensively with the federal ban)
R.W. v. Sanders, 168 S.W.3d 65 (Mo. banc 2005) (definition of ex post facto law)
Johnson v. United States, 529 U.S. 694 (2000) (two-part test for ex post facto challenges)
Lynce v. Mathis, 519 U.S. 433 (1997) (fair-notice concern central to ex post facto analysis)
United States v. Pfeifer, 371 F.3d 430 (8th Cir. 2004) (federal felon-in-possession statute is not ex post facto because it punishes later possession)
State v. Williams, 700 S.W.2d 451 (Mo. banc 1985) (persistent-offender statute not ex post facto where punishment applies to post-enactment offense)
State v. Acton, 665 S.W.2d 618 (Mo. banc 1984) (similar principle that recidivist statutes may rely on antecedent convictions)