The story of Sarah Pederson {"Hit and Run: A Victim's Story," Style, Jan. 10} and the article on the death of Nancy Gardner {Close to Home, Jan. 27} are tragic reminders of crime and violence and the bitterness, frustration and emotional suffering caused by such acts.

Police officers who investigate these crimes suffer as well. Mistakes are occasionally made. But after reading what was written about these investigations, I was alarmed and saddened by the suggestion that they were conducted by incompetent, insensitive and inept investigators who care little about the victims or about apprehending those who committed the crimes. Although neither case has been concluded, the investigations are far from incomplete and cursory. Like the family and friends of Sarah Pederson and Nancy Gardner, investigators are angered by the violence and frustrated by the results thus far.

Rules of evidence, requirements for warrants and successful prosecution and the rights afforded all people -- including those who commit violent crimes -- are invisible and boring realities to victims. However, they are necessary and understandable parameters that sometimes turn what appear to be quick and obvious conclusions into something different and far more time consuming.

Forget the dragnets of yesteryear in which citizens could be incarcerated for "investigative" purposes, the parade of witnesses providing unsolicited information, the hot-light and smoke-filled-room interrogations and the hoards of spontaneous confessions. The burden of success now weighs heavily on the government's ability to develop not just evidence but evidence sufficient to sustain an arrest even if the government believes it knows who committed the crime.

In these cases, witnesses described the crimes but could not sufficiently identify the perpetrators. Physical evidence was collected and analyzed. Leads were pursued to conclusion. And yes, more often than we like and more often than the public suspects, "nobody saw anything."

All of this is nice, and I too reject it as an excuse. I recognize, as do my detectives and others who investigate violence, that the only real satisfaction for victims and their families is arrest and prosecution. We understand and respect that responsibility. Our citizens can be confident that the men and women of their police force have and will continue to serve them well. CAPT. DAVID P. BAKER Commander, Traffic Enforcement Branch Metropolitan Police Department Washington