We study the implications of a structure of the criminal justice system on sentencing decisions. To limit sentencing disparities, offenses are typically divided into subsections with specific sentencing ranges.
The classification into corresponding subsections often depends on exceeding a given quantity threshold, such as drug amount. We study the consequences of these quantity thresholds on sentencing decisions and argue that the threshold effect can be decomposed into two opposing mechanisms: the severity mechanism and the reference one.
An experiment with Czech prosecutors shows that thresholds cause an enormous increase in harshness of sentencing, leading to sentencing disparities. We further introduce empirical measures of (in)justice and quantify the consequences of quantity thresholds on the probability of imposing a just sentence.