It’s not that Pauline Wells wasn’t used to singing: Growing up in a family with strong Irish roots, and a father who loved to sing, there were plenty of opportunities for her at home or in the church choir. But getting up by herself to sing in front of a roomful of people – let alone a packed stadium? Not a chance.

Her husband, however, had other ideas.

“This is all Richard. If not for him, I never would’ve tried,” says Wells, who has made more than 500 public appearances – including at Fenway Park, Gillette Stadium and Faneuil Hall – in nearly 16 years of singing professionally. “I had such huge stage fright. But when we were on the dance floor together, I just quietly sang along to the songs that were playing, and he loved it. He always encouraged me. And then one year, he got me singing lessons as a Christmas present. That was how it started.”

Wells has become an iconic figure in Boston, not only as a singer but also as a police officer – roles she regards as intertwined – performing the national anthem in full uniform at civic, charitable, and other special events. She has headlined benefit concerts (some of which she attends in civilian attire) to support military veterans, foster children, homeless people, and others in need, and she has sung at naturalization ceremonies for new American citizens. Her repertoire includes many familiar Irish and Celtic as well as American songs, contemporary as well as traditional, including the likes of “Fields of Athenry,” “Tell Me Ma,” “Hard Times,” “Ride On” and “Auld Lang Syne.”

On May 11, Wells will perform for a cause that is particularly near and dear to her heart. In observance of National Police Memorial Month, she’ll play at The Burren in Somerville with her friends and frequent collaborators, local band Devri Boston, in a benefit for the New England Chapter of Concerns of Police Survivors (COPS), a nationwide non-profit that provides essential services to the families and survivors of law enforcement officers killed in the line of duty.

A Cambridge police officer for 20 years who has risen to the rank of lieutenant, Wells officially began her singing career in the wake of one of America’s darkest days, the 9/11 terrorist attacks – a date that was, and remains, especially painful for first responders and public safety professionals who lost many of their colleagues. In the weeks that followed 9/11, Wells notes, there was a great demand to have police and fire department representatives provide music at public events. This, she felt, was something she could do – not for herself so much as for her fellow officers and for her country.

Singing the national anthem in places like Fenway Park and Fanueil Hall was a dive into the deep end (“‘Nervous’ doesn’t begin to describe how I felt,” she says), but her singing lessons with Robert Honeysucker, a faculty member at the Longy School of Music, paid off: He had encouraged her to sing as if she were singing just for herself.

“Bob has been such a positive influence,” says Wells. “He’s pushed me in just the right ways.”

She definitely needed some reassurance when, a little more than 10 years ago, she was stricken with a virus that resulted in complete and permanent hearing loss in her left ear. In addition to Honeysucker, Wells credits the renowned Irish tenor Ronan Tynan for his advice and support. And Richard, as always.

Being able to continue with her singing in spite of her hearing loss has been a blessing, Wells says – and being able to use this talent to support worthy causes is another. “Almost every event I do is for charity: That’s the way it started, and I’ve kept with it,” she says. “My feeling is, if paying a performer is one thing a charity doesn’t have to worry about, so much the better.”

Wells will be especially busy this month, appearing at several other police memorial events, including one in Washington, DC, in addition to the COPS benefit on May 11. The dangers that go along with the job of being a police officer or other first responder are always there, but May is a time when the sacrifices of fallen comrades are keenly felt.

Wells thinks, for example, of Sean Collier, the MIT police officer who was killed in a confrontation with the Boston Marathon bombers four years ago. “I met Sean a few times, and he was one of those people you feel you just want to know: a good officer, but more importantly, a good person. I’m proud to sing in his memory.”

There are many others to sing for, not just those who are gone but also those who serve the public day in and day out. That’s why Wells feels that her identities as police officer and singer are not separate, but inextricably linked.

“I started out singing in uniform,” she says, “and I continue to do a tremendous amount of singing in uniform. I never feel as if I’m putting one part of me off to the side. This is who I am.”

For tickets and other details on the May 11 COPS benefit concert, go to brownpapertickets.com/event/2916261. Pauline Wells’s website is paulinewells.com.