Any performance enhancing drugs (steroids) are illegal. The baseball players lied in federal court about taking them. In this country, if you lie in court, you will be in trouble. Thus, all these investigations.
These high profile cases give the illusion that Congress spends the majority of its time on high profile cases. Turn off all your "news and entertainment" TV stations like TMZ and ESPN. If you are that critical of how wasteful congressional hearings are, turn on C-Span. You will soon learn the hours Congress has spent on all the juiceheads is nothing compared to the hours news and entertainment TV has spent and Congress has better things to do like pass laws and bills so that you can lead a life of liberty, equality and the pursuit of happiness.
btw, the congressional hearings on drug and doping scandals are driven by their desire to rid this country of people who are trying to corrupt athletes in all sports, not just baseball. As mothers of children who play sports now and might go on to have a career in professional and amateur sports, I'm pretty sure you will want your kids to be as clean as possible or else we may be wasting our tax dollars on their congressional investigations too, eh?