Sentence reforms enacted by states came to be known as "truth-in-sentencing" statutes. The first such statute was enacted by the state of Washington in 1984. According to William J. Sabol and colleagues at the Urban Institute (The Influences of Truth-in-Sentencing Reforms on Changes in States' Sentencing Practices and Prison Populations, Washington, DC, April 2002), forty-two states and the District of Columbia had enacted some type of truth-in-sentencing statute.
Also in 1984, Congress established the U.S. Sentencing Commission (USSC) in the Sentencing Reform Act. Congress charged this new federal agency with developing sentencing guidelines for federal courts. The Sentencing Reform Act was the federal enactment of truth-in-sentencing.
"Truth-in-sentencing," abbreviated as TIS, is intended to tell the public that a sentence announced by the court will actually be served—rather than the criminal serving only some small fraction of the sentence, the prisoner being released on parole, or the individual having the sentence commuted to probation and serving no time at all. Under TIS statutes, offenders are required to spend substantial portions of their sentences in prison. The federally recommended portion is 85% of the sentence.
With TIS came the distinction between indeterminate and determinate sentencing. Indeterminate sentencing gives parole boards the authority to release offenders at their option after a process of review. Determinate sentencing takes decision-making power away from parole boards, fixes the term to be served, and provides or denies the means to shorten the sentence by good behavior or other "earned" time. Part of the truth-in-sentencing statues are mandatory minimum sentences specified by law for specific offenses and circumstances. Mandatory minima are published in sentencing guidelines, which judges are required to use. Guidelines define the range of sentences the judge may apply, again governed by the offense and the prior history of the offender (e.g., first-time or repeat-offender, severity of the offense, etc.).
Setting uniform sentences for offenses and requiring that fixed proportions of them be served by those convicted put pressure on prison and jail capacities. In response, Congress passed the Violent Crime Control and Law Enforcement Act of 1994, known as the 1994 Crime Act. Its grant program provisions set as a requirement for funding that states have in place truth-in-sentencing statutes. Thus, the federal government provided incentives to states for enacting truth-in-sentencing laws or to conform such laws to the federal sentencing guidelines published by the USSC. Eleven states passed truth-in-sentencing laws in 1995 in response to the federal initiative.
The net effect of federal guidelines, the 1994 Crime Act and its financial incentives, and state actions before and after federal legislation has been to make sentencing more uniform across the nation and, at the state level, to extend the time convicted felons spend in prison.