National Judicial Reporting Program
Survey sampling procedures and definitions of terms
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Note: The following information has been excerpted from U.S. Department of Justice, Bureau of Justice Statistics, Felony Sentences in State Courts, 1998, Bulletin NCJ 190103, pp. 12, 13; 2000, Bulletin NCJ 198821, pp. 11, 12 (Washington, DC: U.S. Department of Justice). Non-substantive editorial adaptations have been made.
Survey sampling procedures
A sample of 300 counties was drawn for the 1988 National Judicial Reporting Program (NJRP) survey. With little exception, these same 300 counties were the source of NJRP data for 3 subsequent NJRP surveys (1990, 1992, 1994). For the 1996 NJRP survey a new sample was drawn, consisting of 344 counties. The 344 counties included 98 that had been in the NJRP sample in the 4 previous surveys (1988, 1990, 1992, 1994) and 246 that had never been part of an NJRP sample. The 98 consisted of 80 counties selected by chance alone; plus 18 of the Nation's largest counties selected not by chance but (given their large 1995 population size) with certainty. The same 344 counties were used for the 1998 and 2000 NJRP surveys.
The 2000 survey used a two-stage, stratified cluster sampling design. In the first stage the Nation's 3,195 counties or county equivalents were divided into 14 strata. Each county was assigned to one stratum by meeting the conditions for that stratum.
The stratum to which a county was assigned depended on three criteria:
1. Whether the county was among the Nation's 75 largest according to 1995 resident population,
2. Ease of data collection (in a State where data collection is generally not costly; one where data collection is generally moderately costly; one where data collection is generally very costly),
3. The size of the county's 1995 resident population.
The largest 75 counties in the United States (as defined by 1995 resident population) were separated from the Nation's 3,195 counties or county equivalents. Each State was then assigned a "cost-factor" that reflected the overall ease or method of collecting their data. Next, counties in each"cost-factor" group were separated into categories based on the size of their 1995 population. This resulted in 13 strata from which a sample of 325 counties was drawn. The 14th stratum consisted of the 19 counties with the largest populations in 1995; every county in this stratum was selected.
The final sample included 344 counties: 45 out of the 75 largest counties and 299 out of the remaining 3,120 counties. Because the 75 largest counties account for a disproportionately large amount of serious crime in the Nation, they were given a greater chance of being selected than the remaining counties. None of the counties refused to participate.
At the second stage of sampling, a systematic sample of felons sentenced for murder or nonnegligent manslaughter, sexual assault (including rape), robbery, aggravated assault, burglary, felony larceny/motor vehicle theft, fraud/forgery/embezzlement, drug trafficking, drug possession, weapons offenses, and other offenses was selected from each county's official records. The total sample numbered 429,471 cases. Of these, 272,889 cases were in the 75 largest counties.
Rates at which cases were sampled varied by how the data were submitted, by stratum, and by crime type. Among counties in States that submitted electronic data, all cases were typically included regardless of the offense type. Among counties in States that either submitted electronic data that required manual processing time or had data from jurisdictions that were collected manually (on-site), a sample of the cases was taken.
The survey targeted and recorded initial sentences imposed in 2000. If a sentence was imposed on one date and then modified at a later date, the revision was ignored. The survey recorded sentences that were actually executed and excluded suspended sentences. If a prison sentence was initially imposed but immediately suspended in its entirety, the case was coded as probation because that was the actual sentence.
Because the year of conviction was not a defining characteristic, some cases in the sample involved persons convicted before 2000, but not sentenced until 2000.
In 34 counties it was impractical to target sentences imposed in 2000. Cases sampled from these counties were all sentenced in 1999.
The 2000 conviction data that were submitted by four Illinois counties were very different from prior years' NJRP data files as well as other court data sources. Consequently, the conviction data submitted by these counties for the 1998 NJRP survey were used in place of the 2000 data.
In 2000, Missouri was unable to provide data for seven counties in the sample. These counties were replaced with seven others in the same respective strata.
The second stage weights for two sampled counties from Florida were adjusted to account for less than a full year of reporting.
Based on these sampling methods, an estimated total of 924,700 persons were convicted of a felony in State courts in 2000.
Sources of data
For 61% of the 344 counties sampled for the 2000 survey, NJRP data were obtained directly from the State courts. Sources of data from other counties included sentencing commissions, statistical agencies, departments of public safety, probation departments, State police departments, and departments of corrections. Individual-level NJRP records were obtained either electronically (83% of the counties) or manually (17% of the counties). Electronic methods of data submission included: diskettes, magnetic tape, and Internet transmission. Manual methods included photocopies of official documents, survey questionnaires completed by court officials, and on-site collections. All data were collected by the U.S. Census Bureau.
NJRP data were obtained from a sample and not from a complete enumeration. Consequently, they are subject to sampling error. A standard error, which is a measure of sampling error, is associated with each number reported. In general, if the difference between two numbers is at least twice the standard error of that difference, there is at least 95% confidence that the two numbers do in fact differ; that is, the apparent difference is not simply the result of surveying a sample rather than the entire population.
National estimates of the number of convictions for individual crime categories and for the aggregate total had a coefficient of variation of 3.6%. Standard errors did not take into account missing data, which are substantial for certain tables.
Before the sample was drawn, each felon sentenced in the sampled counties in 2000 was placed into 1 of the 11 offense categories identified above. If the felon was convicted of more than one felony offense, the offense category was the most serious offense. The hierarchy from most to least serious offense was murder, sexual assault, robbery, aggravated assault, burglary, drug trafficking, weapons, forgery/fraud/embezzlement, larceny/motor vehicle theft, drug possession, and all other felonies. The hierarchy was determined from an analysis of two factors that reflect how seriously the justice system treats different offenses: the sentence length imposed and the time actually served in prison before release. In general, the higher the offense is in the hierarchy, the more serious it is in terms of the two factors. Sample selection procedures gave each sentenced felon a single chance to be in the sample. However, felons who appeared in court on more than 1 day for different offenses and received a sentence at each reappearance had more than a single chance.
At the data analysis stage, cases were aggregated according to their offense designation at time of sampling, with the single exception of "other violent." "Other violent" is a category shown in the tables, but it was not a category at sampling. The "other violent" category was formed from the sampling category "other felonies." That is, after sampling, sampled cases designated "other felonies" were coded either "violent," "nonviolent," or "not ascertained," based on data available. Cases coded "not ascertained" were rare. For data analysis purposes, cases coded "other violent" were removed from the "other felonies" category and shown separately in the tables. The offense categories shown in the tables are defined as follows:
Murder and nonnegligent manslaughter--Murder is (1) intentionally causing the death of another person without extreme provocation or legal justification or (2) causing the death of another while committing or attempting to commit another crime. Nonnegligent (or voluntary) manslaughter is intentionally and without legal justification causing the death of another when acting under extreme provocation. The combined category of murder and nonnegligent manslaughter excludes involuntary or negligent manslaughter, conspiracies to commit murder, solicitation of murder, and attempted murder.
Rape and sexual assault--Rape includes forcible intercourse (vaginal, anal, or oral) with a female or male. Includes forcible sodomy or penetration with a foreign object (sometimes called "deviate sexual assault"); excludes statutory rape or any other nonforcible sexual acts with a minor or with someone unable to give legal or factual consent. Includes attempts. Other sexual assault includes (1) forcible or violent sexual acts not involving intercourse with an adult or minor, (2) nonforcible sexual acts with a minor (such as statutory rape or incest with a minor), and (3) nonforcible sexual acts with someone unable to give legal or factual consent because of mental or physical defect or intoxication. Includes attempts.
Robbery--The unlawful taking of property that is in the immediate possession of another, by force or the threat of force. Includes forcible purse snatching but excludes nonforcible purse snatching, which is classified as larceny/theft. Includes attempts.
Aggravated assault--(1) Intentionally and without legal justification causing serious bodily injury, with or without a deadly weapon or (2) using a deadly or dangerous weapon to threaten, attempt, or cause bodily injury, regardless of the degree of injury, if any. Includes attempted murder, aggravated battery, felonious assault, and assault with a deadly weapon.
Other violent--Violent offenses excluding murder and nonnegligent manslaughter, rape and sexual assault, robbery, and aggravated assault. Includes offenses such as kidnaping, extortion, and negligent manslaughter. Includes attempts.
Burglary--The unlawful entry of a fixed structure used for regular residence, industry, or business, with or without the use of force, to commit a felony or theft. Includes attempts.
Larceny--The unlawful taking of property other than a motor vehicle from the possession of another, by stealth, without force or deceit. Includes pocket picking, nonforcible purse snatching, shoplifting, and thefts from motor vehicles. Excludes receiving and/or reselling stolen property (fencing) and thefts through fraud or deceit. Includes attempts.
Motor vehicle theft--The unlawful taking of a self-propelled road vehicle owned by another. Includes the theft of automobiles, trucks, and motorcycles but excludes the theft of boats, aircraft, or farm equipment (which is classified as larceny/theft). Also includes receiving, possessing, stripping, transporting, and reselling stolen vehicles and unauthorized use of a vehicle (joyriding). Includes attempts.
Fraud, forgery, and embezzlement--Using deceit or intentional misrepresentation to unlawfully deprive a person of his or her property or legal rights. Includes offenses such as check fraud, confidence games, counterfeiting, and credit card fraud. Includes attempts.
Drug possession--Includes possession of an illegal drug, but excludes possession with intent to sell. Includes attempts.
Drug trafficking--Includes manufacturing, distributing, selling, smuggling, and possession with intent to sell. Includes attempts.
Weapons offenses--The unlawful sale, distribution, manufacture, alteration, transportation, possession, or use of a deadly or dangerous weapon or accessory.
Other offenses--All felony offenses not listed above. Includes receiving stolen property, driving while intoxicated or other traffic offenses, bribery, obstructing justice, escaping from custody, family offenses (such as child neglect, contributing to the delinquency of a minor, nonpayment of child support), and nonviolent sexual offenses (such as pornography offenses, pimping, prostitution). Includes attempts.