No, the investigation, once launched, can create preconditions for possible breaches of law, regardless of whether the primary target "crime" is ever charged. The coming indictments will be for coverup activities - perjury, obstruction of justice. Special prosecutors, folks like Starr and Fitzgerald, I assume to be acting in a non-partisan fashion, look for violations of law and try to prosecute them.
Admittedly I am a partisan, but my sense is that there will be a large "technicality" component to these charges.