DNA typing produces a pattern called a DNA profile. If the bands in the profile line up with those in the trace evidence, within a specified margin of error, there is a match. While DNA matching evidence is probative, a match only estimates the probability that a defendant is the source of the sample. DNA samples are often used in paternity cases, but the analysis cannot tell the likelihood that an alleged father is the true father of a particular child. Laboratories may claim a 50 percent prior probability assumption, but that is misleading and could be prejudicial to the defendant. Furthermore, probability estimates made by laboratories do not allow for genetic similarities in source or suspect populations. The two major categories of error in DNA fingerprinting include false positives and false negatives. This author argues that laboratories should be required to provide conservatively high estimates of their false positive error rates when providing genetic matches, as well as information on false negative error rates when reporting an exclusion. 1 figure and 24 notes