Blood Test Law and Legal Definition

A blood test is a scientific evaluation of blood drawn from a person for a variety of reasons. Blood tests are commonly performed to determine a child's biological parents or to test for sexually transmitted diseases. In a paternity blood test, the DNA samples of the allgeed father and child are compared side-by-side for matching characteristics. If the man tested is the biological father of the tested child, his probability of paternity will be 99% or higher.

A blood test is required in some states as a precondition to obtaining a marriage license. Some states allow a person suspected of DUI/DWI to be required to submit to a blood test to determnie the presence of alcohol or controlled substances. Laws vary by state, so local laws should be consulted for specific requirements in your area.