Academics sometimes make the mistake of thinking that their standards do not need to be particularly high when writing for the public. Even though you will not be writing with the precision of scholarly prose or citing every source, you should still strive to be as accurate and careful as you would be in your scholarly publications, especially if you are drawing on your specialization.
The uncomfortable reality is that — while crossover work counts for little in the way of raises or promotions in academe — it can still hurt your reputation if you do a sloppy job.
Given all of those warnings, why write for the public at all?
There are strategic reasons, such as raising your visibility or showing the relevance of your research. It is also satisfying to reach readers who are curious about your field, but do not have the training necessary to appreciate your scholarship. As a public scholar, you have the freedom to write about topics beyond your area of specialization, which in turn can enrich your research and teaching. Finally, many of the qualities that make for good public essays — clarity, conviction, style — can improve your scholarly writing too.