The Len Bias laws refer to a series of laws passed after the death of Len Bias. The previous posts have done an excellent job in assessing these laws. I think that you could really expands this in examining the time and social context of the Bias law. The death of Len Bias to cocaine was set in stark contrast to Bias, himself. The promising young athlete, the savior of the Boston Celtics, and the very idea of being the type of young man that parents wanted their sons to be and their daughters to marry were all smashed to pieces with his death due to cocaine. The resulting laws were more of a part of "the war on drugs," where the public believed that "getting tougher" on drugs and laws that featured harsher penalties would remove the drug problem from the United States. Like Bias itself, the laws reflected that the drug problem needed deeper analysis and understanding than superficial gestures. Perhaps then, a "Len Bias Law" would be any law or legislation passed in the wake of an event that has garnered national attention which seeks to address or solve the problem that gave rise to it.
Len Bias was a basketball player at the University of Maryland when he died of a cocaine overdose. After his death, "Len Bias Laws" were enacted. Simply put, these laws make people who illegally manufacture, distribute, or sell illegal drugs strictly liable for a death that results from the inhalation, injection, or ingestion of the drug they are associated with.
If a drug dealer sells an illegal substance to a person, that person takes the drug and then dies as a result of taking the drug, the dealer can be charged with murder. Obviously this is easier said than done because of the covert nature of the drug trade.
A good example is this, say you bought cocaine and shared it with your girlfriend, she ingested it and died. You could be charged with murder because you supplied her with the illegal substance.
There are a couple of possible answers here.
Len Bias was a really good basketball player who was the first pick in the 1986 NBA draft. But before he actually got to the NBA, he died of a cocaine overdose. In his memory, a couple of laws or kinds of laws were passed.
The first of these was simply a new general drug law that was passed not long after his death. Some called it the Len Bias law, but I do not think that is what you are asking about.
The second is a type of law which holds the drug dealer legally responsible when he sells drugs to someone who then dies from them or is significantly harmed by them. The idea here is that the dealer has caused the harm to the person and should therefore be responsible not just for selling the drugs, but also for the damage done by those drugs. I think this is what you are asking about.
For more details, follow the link and then search for "Len Bias" within that page.