I do not really think that this is a civil rights complaint. Police departments have the authority to refuse to investigate or charge offenses all of the time and there is nothing that we as citizens really have as a recourse, except for asking the local District Attorney to look into it. You might want to address with with the El Paso County DA's Office run by Dan May. They have numerous people who handle complaints such as your's about officers not following through with case. The DA is the chief law enforcement officer is any judicial district.