It is my pleasure to present retired Federal Prosecutor and former AUSA for the District of Columbia, Marc Rainer, author of several crime dramas, including the fourth book in his Jeff Trask series, A Winter of Wolves, recently released October, 2016. Mr. Rainer arrives at Sherrie’s Always Write to discuss the delicate mixture of fictional crime writing with his dramatic legal career.

The Author and The Expert

written by Marc Rainer

After more than three decades as a federal prosecutor, and after several years as an author, I often find myself noting similarities between the professions. One of my most recurring impressions is the floating nature of the subject matter faced by both occupations. Both the law and writing are essentially overlays, merging with another profession or topic in an attempt to create a result: a favorable verdict regarding one topic, a compelling novel regarding another. An attorney, after all, is called upon to be an advocate, but the topic of that advocacy varies from case-to-case. As a federal prosecutor, I represented the people of the United States, but the subject matter of that prosecution could be drug dealing, a murder, money laundering, or a criminal conspiracy. As a writer, I tell stories — stories that are based on cases and criminals I’ve encountered — and those stories often parallel the variety of cases I tried, each with distinct matters of evidence.

These cases and plot lines often involve dealing with forensic issues, and with the experts who must take the stand to explain such proof to the jury. Whether the expert was one of my own witnesses who was going to present evidence favorable to my case, or a defense expert whom I would have to cross-examine, the forensic issue at hand was a topic I had to study. In short, I had to become an expert on that subject matter myself, in order to either present or attack the expert testimony. It might be fingerprint evidence in one case, DNA in another, tool mark or ballistics evidence in yet another case, serology in another. In some cases, all of these types of proof were involved. In several cases, the defense tried an insanity defense, bringing psychiatric issues into play.

We are told by successful writers to write about what we know. This allows us to approach a topic or a scene with credibility. That does not mean that we stop learning, or that we approach our field of potential topics frozen at any point in time to what we know at that point in time. We can – and should – grow in knowledge, and in what we know, thereby expanding our horizon of writing topics. Perhaps the biggest difference between my two careers is that – as an attorney – I had to react to the demands of a given case, learning about the issues inherent in that dispute. As a writer, on the other hand, I can choose those issues.

How – younger attorneys have asked me – do I prepare to cross-examine a psychiatrist? How do I match wits with an expert who has years of training and experience? How can I ever hope to know more than that doctor about psychiatry? My answer was that they were asking the wrong question. Of course, they could not become an expert in the field of psychiatry in a month or two before trial. They could, however, hope to level the playing field against the expert by first identifying the very limited piece of psychiatry applicable to the upcoming trial, and by studying the hell out of that much more limited issue.

I tried a murder case once in which the proof against the defendant was overwhelming. Witnesses, motive, and evidence all conclusively identified the defendant as the killer. There was only one defense left to him at trial: insanity. We worked hard as an investigative team to sift through the defense experts’ paperwork and first identify which “mental disease or defect” the defense was hanging their collective hats on. Once that was accomplished, our study of paranoid schizophrenia was much more manageable than trying to earn psychiatric degrees ourselves. Thousands of pages of literature was suddenly limited to hundreds, then a few critical dozens. Working with our own experts to identify weaknesses in the defense experts’ approach to the case, we were able to destroy the defense at trial. The actual transcript of that cross-examination was used in the conclusion of my first crime drama, Capital Kill.

“Both the law and writing are essentially overlays, merging with another profession or topic in an attempt to create a result” – Marc Rainer

Writers wishing to incorporate forensic proof and issues into a crime thriller can use the same approach. It is not necessary to earn a certificate in forensic sciences or perform years of work as a crime scene technician in order to write about any forensic technique or issue in a novel. In the digital age, a trip to the library might not even be required.  The links from one internet article to another often provide a wealth of information, contrasting views, and fairly complete courses of instruction on focused, narrow, issues. The final step, in every case, should be a consultation with true experts in the field to make sure that the writer’s conclusions are accurate. The author’s credibility – and future book sales – might depend on it.

As the plot of a novel takes the author in unexpected directions, that writer should not be afraid of venturing into what was initially an unknown realm. If fingerprints become an essential topic in a plot line as that story develops, the author can – with a bit of study and consultation – write about what he or she knows, even if that knowledge is new.

If you enjoyed today’s deep dive into the culmination of legal, crime, and forensics in writing, feel free to leave a comment below.

Marc Rainer Biography

Marc Rainer (the author’s pseudonym) was born in Hattiesburg, Mississippi in 1951. He is a graduate of the United States Air Force Academy and a former Air Force JAG and retired federal (civilian) prosecutor. 

In 1987, he left active duty and accepted an appointment as an Assistant United States Attorney (AUSA) for the District of Columbia, where he prosecuted “street crimes” in the District’s Superior Court, was promoted to the District Court (federal) division, and served on the trial teams in major drug cases, including the prosecution of Jamaican “Posses.” He moved to the Western District of Missouri in 1990, and continued his practice as a federal prosecutor in Kansas City until his retirement in 2015.

He lives in a suburb of a major northwestern city with his wife, a former Air Force OSI Special Agent, and their three rescued dogs.

If you would like to explore Marc Rainer’s crime dramas firsthand, visit his website at or on Amazon.

“As good as anything I’ve read in courtroom fiction.” – The Reporter

A Winter of Wolves available on Amazon


All 4 Jeff Trask Novels from Amazon



Sherrie’s Always Write