Section 40 StGB requires the additional sentence, within the limits of section 31, to be set so that the sum of the earlier and new sentences corresponds to the sentence that would have been imposed after a joint trial. The court must therefore carry out a hypothetical joint sentencing assessment.
The additional sentence may not exceed the statutory maximum threatened for the offence tried later. At the same time, the total of both sentences may not exceed the limit arising from the rules on concurrent offences and the aggregation of values or amounts of loss.
If a joint trial would not have justified a sentence higher than the sentence in the earlier judgment, section 40 StGB provides that no additional sentence is imposed. The later decision can therefore result in an additional sentence of zero even though the later offence is adjudicated.