The Boston Herald today follows up its social-media story with more from Dave Wedge and Jessica Heslam and a column by Margery Eagan.

In order to bolster her argument that Amy Derjue, spokeswoman for Boston City Council president Mike Ross, is tweeting when she ought to be working, Eagan quotes something Derjue posted on Monday at 10:11 p.m.

I’m not here to defend Derjue, Mac Daniel or David Isberg, who have created something of an appearance problem for their bosses, even though I’ve seen no real evidence that they’ve been slacking off. (In fact, I think Heslam gets at the appearance problem nicely here.)

But quoting something a city employee posted at a time when she was clearly off-duty is out of bounds.

Amy Derjue (from Twitter)

Adam Gaffin of Universal Hub has some big-time fun with the Boston Herald’s story on city employees who use Facebook and Twitter during work hours. Gaffin reproduces a photo of the Herald reporters who wrote the story, Jessica Heslam and Dave Wedge, from — yes — Heslam’s Facebook account.

“What are they using them for?” asks Gaffin. “What are they hiding? Ooh, insinuation is fun!”

Kidding aside, you have to admit that there’s an appearance problem with the way some city employees are using social media. Heslam and Wedge focus on Amy Derjue, a former Boston Magazine blogger who was hired earlier this year to serve as City Council president Mike Ross’ $39,000-a-year spokeswoman.

Derjue is something of a young-woman-about-town, and I follow her on both Facebook and Twitter. (If you page through her 340 Facebook friends, you’ll see a wide array of local media and political folks, including Gaffin, me — and Wedge.) Some of her posts make me cringe, and Heslam and Wedge dutifully provide some cringe-worthy examples. But I’ve never heard anyone suggest she wasn’t smart, hard-working and energetic. For what it’s worth, she has complained to me on behalf of her boss, which suggests dedication to her job.

More to the point, most of us — and you can be sure Derjue falls into this category — are never fully off work. If we’re expected to tend to business when we’re off-duty, then we have to be allowed some fun during the formal workday as well. And, as Gaffin writes, “Why, it takes sheer seconds to post something to Facebook or Twitter.”

An aside that may help illustrate my point. Yesterday John Robinson, editor of the News & Record in Greensboro, N.C., tweeted that he was being yelled at by a “legislator who resigned in disgrace.” When I responded at how impressed I was with his multi-tasking, he replied, “Yes, tweeting while yelling. What else am I supposed to do? Listen?” This was not a private conversation — it was seen by all 1,196 of Robinson’s followers and all 2,019 of mine. Welcome to 2009.

Ross tells the Herald that he hired Derjue in part for her social-networking expertise. And, indeed, Ross has a pretty lively Twitter feed and Facebook account. For Derjue to post to her personal sites while working on her boss’ would, as Gaffin says, take “sheer seconds.” You can question her judgment, but her social-media activities are not evidence of dereliction.

Derjue seems to have partly disabled her Facebook account (I could be wrong; Facebook mystifies and annoys me), and she hasn’t posted to Twitter since last night. No doubt she’s licking her wounds at the moment. I’m interested to see how she’ll respond.