Without the help of feedback explaining why they didn’t rate, future positions may prove elusive for such eager applicants. Yet, because of laws that protect applicants from discrimination, employers’ tongues are tied. It’s the No. 1 complaint Steve Lowisz hears from candidates as founder and CEO of Michigan-based recruitment firm Qualigence. Though most applicants would appreciate some candid and constructive criticism, a recent study by the Talent Board, a nonprofit that works to improve recruiting practices, indicates that only 4.4% of more than 2,000 participants received specific feedback from hiring managers and recruiters.

Radio silence doesn’t only have to do with lawsuit worries, Lowisz says. It has plenty do with laziness. Many companies rely on standard jargon generated by their applicant tracking system for the so-called Dear John letter.

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Staying mum could also lead to a missed opportunity for the hiring company. Open communication can help build and maintain relationships with candidates who could be recruited in the future. Even if they never become part of the staff, applicants will remember the manager who took the time to do a bit more to help. A rejected applicant might even refer other qualified candidates or become a loyal customer.

Although giving feedback to rejected job applicants is not a practice employment lawyers would recommend, Joseph Harris, a partner at law firm White Harris says if you are going to do it, focus on the essential functions of the job and its core requirements. This could help candidates with future applications and interviews.

There are, of course, some things that shouldn’t be mentioned at all. Lack of charisma or chemistry with the interviewing team, as well as other unsavory behaviors that the applicant’s parents should have nipped in the bud shouldn’t be brought up.

Avoid comments about a candidate’s dress or appearance, says Mark Girouard, an employment attorney at Nilan Johnson Lewis in Minneapolis. What might seem like an innocent comment about a hairstyle or outfit choice could be misperceived as a reference to the applicant’s membership in a protected class.

Empathic interviewers might anticipate questions from rejected applicants such as, “What could I have done differently that would have gotten me the job?” Emphasize to the rejected candidate that you can’t get into a debate, but that you have time to offer one piece of advice. Let the person know what they did well, so they can make use of that strength during their next interview.

Phone calls offering advice can be risky, as the rejected applicant is likely to ask questions the employer may not be prepared to answer, Harris explains. If you must use the phone, he advises making sure there is another representative of the employer on the line to be a witness.

For instance, one employer in New York City told an applicant in a casual phone call that they were rejected because they hadn’t been working for the past six months and the employer wanted to hire someone with more recent and ongoing experience. “Though this may sound like reasonable feedback, as of June 11, 2013, discrimination against the unemployed is illegal in New York City, and the employer’s comment may be actionable,” says Harris.

Another way to help would be to ask a candidate where they believed they might have done better in the interview, or demonstrated more compatibility with the position. This offers them a chance to work through problem areas while giving the hiring manager a better sense of the candidate’s self-awareness. This could be valuable in more ways than one, if the person decides to reapply for a job at the company.

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Even the best intentions can lead to disaster, though. Management and HR consultant Abhay Padgaonkar recently saw a letter sent by the hiring team at a large technology firm that offered educational references so the rejected candidate could sharpen their technical interviewing skills before applying again. “At the end of the email was a listing of 20 different books in three different areas,” Padgaonkar explains. “Dumping a list of 20 books for self-improvement is hardly helpful,” he contends.

Then again, sending someone a thoughtfully chosen link to an article on a concept that hints at the key areas a candidate needs to work on might be the wink that gets past the lawyers and into a grateful applicant’s interview toolbox.

Harrison Monarth is the founder of GuruMaker — School of Professional Speaking. He’s also the author of The Confident Speaker and Executive Presence.