Why did former girlfriends of some athletes become targets of investigations?

Certain sportspersons that are suspected of steroid use become targets of the government. Feds do almost anything in order to determine whether several athletes have taken any doping products. They don’t spare taxpayers’ funds for this purpose. Much money is wasted to disclose even private life of athletes. According to the government, some details of their private behavior can reveal the truth about administration of forbidden drugs. Thus, girlfriends of some sportspersons are interviewed by federal prosecutors.
For example, it has been revealed that former girlfriends of Lance Armstrong and Roger Clemens and a former mistress of Barry Bonds have been asked about certain details linked with private life of these athletes. Which questions were asked?
Kimberly Bell, a former mistress of Barry Bonds, was asked about testicles of this baseball player. She reported that the athlete’s testicles were shrunken. So, her words served as a proof that Barry Bonds administered steroids and/or other prohibited products.
It is known that shrinkage of testicles belongs to unwanted consequences of several steroids. So, the government decided to find out whether Barry Bonds had had this problem. But it is an unreliable argument in order to prove that someone has applied some banned medicines. Consumers of steroids may prevent this side reaction, if they apply some medications for this purpose.
Mindy McCready, a former mistress of Roger Clemens, was asked whether this former athlete had had erectile dysfunctions. The woman said that sometimes Roger Clemens had suffered from this problem.
When it comes to erectile dysfunctions, they may occur during application of steroids. But if you study information about adverse reactions of steroids more attentively, you can understand that this effect is more likely to appear after discontinuation of administration. It happens because natural testosterone production is normally suppressed by application of exogenous testosterone. But since there are such medications which have capacity to regenerate natural production of testosterone, erectile dysfunctions can be avoided.
Sheryl Crow, a former girlfriend of Lance Armstrong, was also interviewed by feds. But questions have not been made public. According to some suggestions, she might have been asked also about sexuality of the cyclist.
Actually, the government has a mistaken point of view in this case. However shrinkage of testicles and erectile dysfunctions may occur because of steroids, these arguments are not suitable.