TAMPA — Most who tuned in to the Tampa Police Department's Nov. 28 news conference broadcast live on television and social media immediately learned of the arrest of a suspect in the killing of four in Seminole Heights.

But the deaf or hearing impaired watched in confusion.

There was an American Sign Language interpreter on camera at the news conference, but little of what she signed made sense.

"She sat up there and waved her arms like she was singing Jingle Bells," Rachelle Settambrino, who is deaf and teaches ASL at the University of South Florida, said Sunday through an interpreter.

"I was disappointed, confused, upset and really want to know why the city of Tampa's chief of police who is responsible for my safety and the safety of the entire community did not check her out."

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Settambrino is not alone in her confusion.

"We did not request an interpreter for a news conference on the 28th," TPD spokesperson Janelle McGregor said, identifying the individual as Derlyn Roberts. TPD is conducting an internal review to determine "who sent this particular interpreter to the news conference to provide services."

Roberts could not be reached Sunday for comment.

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TPD had a new interpreter, Ben Zapata, for the Nov. 29 news conference about the murders. He was hired through Purple Communications, McGregor said, a company TPD typically uses for its ASL interpreter needs.

Settambrino said that according to interpreter Roberts, Tampa Police Chief Brian Dugan at one point said the following:

"Fifty-one hours ago, zero 12 22 (indecipherable) murder three minutes in 14 weeks ago in old (indecipherable) murder four five 55,000 plea 10 arrest murder bush (indecipherable) three age 24."

What he was explaining was a time line of the four murders and how TPD received over 5,000 tips in the case before they arrested the 24-year-old suspect.

Some but not all networks had closed captions for the news conference, but the hearing impaired typically focus on the interpreter, Settambrino said and that when it comes to information sharing, "we are being marginalized."

Windy Rossi, an ASL interpreter in Texas, was notified of Roberts' work by a friend's Facebook post, so she tuned in to see it for herself.

She asked, "Is this a systematic problem in Florida?" citing how as Hurricane Irma threatened the state an ASL interpreter at a Manatee County news conference was unqualified to provide needed safety precautions. At one point that interpreter signed "Bear monster," according to news reports.

Settambrino said there is an issue in Florida because this state, unlike some others, does not require ASL interpreters to be certified through the Registry of Interpreters for the Deaf, a national nonprofit that, according to its website, "seeks to uphold standards, ethics, and professionalism" for that field.

"They only say (ASL interpreters) have to be qualified," Settambrino said of Florida. "But what is that definition of qualified?"

To be certified, Lissette Molina Wood, past president of the Florida Association of the Deaf and who is deaf, said through an interpreter that individuals need a bachelor's focused on sign language and interpretation.

At USF, such degrees are earned through the Department of Communication Sciences & Disorders.

Then, they must pass a three-part test through the Registry and continue to take classes to maintain and upgrade that certification.

Rossi, the interpreter from Texas, said she has a master level certification.

Zapata, who took over the duties for TPD on Nov. 29, lists the same credentials on his LinkedIn page.

Former FAD president Wood said the Florida Legislature has been unsuccessfully lobbied to pass a bill requiring all ASL interpreters be certified.

Settambrino and Wood spoke to the Tampa Bay Times through certified interpreter Carrie Moore at the International Mall's "Signing Santa" event that provided deaf and hard of hearing kids the opportunity to meet Santa.

If a fun event hires only certified ASL interpreters, serious ones should too, Wood said. "I am hoping the time is now for the bill."

Times web producer Kirby Wilson contributed to this report. Contact Paul Guzzo at pguzzo@tampabay.com. Follow @PGuzzoTimes.