"Justice Breyer delivered the opinion of the Court in part, concluding that 18 U. S. C. A. §3553(b)(1), which makes the Federal Sentencing Guidelines mandatory, is incompatible with today's Sixth Amendment 'jury trial' holding and therefore must be severed and excised from the Sentencing Reform Act of 1984 (Act). Section 3742(e), which depends upon the Guidelines' mandatory nature, also must be severed and excised. So modified, the Act makes the Guidelines effectively advisory, requiring a sentencing court to consider Guidelines ranges, see §3553(a)(4), but permitting it to tailor the sentence in light of other statutory concerns, see §3553(a)."

Source

Decision of the United States Supreme Court, United States v. Booker, Case No. 04-104, Argued Oct. 4, 2004, Decided Jan. 12, 2005.
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