As a lawyer for George Zimmerman, Mark O'Mara was a familiar figure for television viewers. His new-found fame highlights the phenomenon of the celebrity lawyer and their role in the US legal system.

For two weeks, television viewers watched the trial of George Zimmerman, the Florida neighbourhood vigilante accused of second-degree murder.

Defence lawyer Mark O'Mara said that Mr Zimmerman had acted in self-defence during his encounter with the unarmed black teenager Trayvon Martin, 17, in a gated community in Sanford, Florida, in February 2012.

The chief prosecutor said that Mr Zimmerman "wanted to make sure that Trayvon Martin didn't get out of the neighbourhood". Mr Zimmerman shot Martin through the heart and killed him.

The jury accepted self-defence as justification for the shooting. The trial resulted in freedom for Mr Zimmerman - and in a new profile for O'Mara.

Image caption People around the world watched the trial - and mourned the death of Martin

O'Mara, a graduate of Florida State University College of Law and a legal analyst for a local television station, WKMG Channel 6, was catapulted into the international spotlight.

His fame, or notoriety, was ratcheted up even more after the trial. Throughout the legal proceedings Mr O'Mara had followed the judge's instructions to keep race out of the court.

After the jury reached their verdict, Mr O'Mara spoke at a news conference - and surprised people with his inflammatory comments about race.

If Zimmerman had been black, said Mr O'Mara, "he never would have been charged with a crime".

This is [Mark] O'Mara's 15 minutes of fame Laurie Levenson, Loyola Law School

"This became a focus for a civil rights event, which again is a wonderful event to have," O'Mara said.

"But they decided that George Zimmerman would be the person who they were to blame and sort of use as the creation of a civil rights violation," Mr O'Mara said. "The facts that night were not borne out that he acted in a racial way."

Many people found his remarks offensive.

"The defence looked unfeeling and callous during the trial," says Jeannine Bell, a professor of law at Indiana University. "This comment - that if Zimmerman had been black, he would not have been charged - reinforced that view."

Image caption Michael Mansfield QC, shown in London in 2008, is a celebrity lawyer in the UK

Others are more blunt. "One of the most infuriating and insulting comments to come from Zimmerman's legal team," writes Dallas Morning News editorial writer Jim Mitchell.

Mr O'Mara may have appeared callous, yet his remarks fuelled his fame. It is not clear how long he will stay in the limelight, though.

During the trial, Mr O'Mara seemed to be following the path of celebrity lawyers who had gone before him.

Gloria Allred, the late Johnnie Cochran, Robert Shapiro and others became household names during the 1994 trial of former American football player OJ Simpson, who was accused of murdering Nicole Brown Simpson and Ronald Goldman.

These lawyers parlayed their work on the Simpson trial into careers in law and the media. Television is their platform.

Image caption Winona Ryder has been represented by celebrity lawyer Mark Geragos

An individual's fate is decided by a jury that has been sequestered. Yet the trials themselves play an educational role for the public, and for that reason they are sometimes televised. That creates celebrities.

In countries where trials are not televised, there are few high-profile lawyers.

The UK has celebrity lawyers such as Michael Mansfield QC and solicitor Imran Khan, both of whom assisted the family of black teenager Stephen Lawrence, who was stabbed to death in 1993.

Yet most UK lawyers are not well known. They work in obscurity.

Image caption Piers Morgan asked Robert Shapiro, Simpson's lawyer, about Zimmerman's trial

In contrast the super-lawyer is part of the legal landscape in the US. They represent famous people, and they become celebrities in their own right.

Allred frequently gives news conferences for her clients. It is a colourful cast that includes Natalie Khawam, who appeared in a scandal involving former CIA director David Petraeus, as well as a porn actress, Joslyn James, who had been involved with Tiger Woods.

Another celebrity lawyer, Mark Geragos, who has represented Winona Ryder and Michael Jackson, "loves the media", according to a New York Times reporter. During one 24-hour period, Geragos received more than 600 calls from journalists.

Lawyer Laura Wasser, who has represented Angelina Jolie, appeared in an Elle magazine photoshoot and served as a legal adviser for Jim Carrey's film Liar, Liar.

Image caption Robert Shapiro, left, became well known during the trial of OJ Simpson

Lawyers are supposed to be discreet. Not surprisingly, many people disapprove of those who play to the media. "It's an erosion in the professional identity of lawyers," says Richard Sherwin, the author of When Law Goes Pop.

"Interviews on the courtroom steps used to be frowned upon," he says. "Now it's a tool that lawyers used to advance their client's interest."

It may be an erosion of values, but it is hardly a new phenomenon. In the late 1890s and early 1900s Clarence Darrow was a celebrity lawyer.

Mr Darrow used the lecture circuit, rather than Twitter, to express his views, but the overarching goal of self-promotion - and amplification of views - remains the same.

Image caption Joslyn James, right, appeared at a news conference with lawyer Gloria Allred

"Celebrity lawyers have an agenda," says Laurie Levenson, a professor at Loyola Law School in Los Angeles, California. "They know exactly what they want to use the media for."

Mr O'Mara's racially charged comments at the news conference after the trial may have been an honest expression of his views but were not "helpful" to his client, says Ms Levenson.

"Being on camera in a press conference is not the time to vent," she says. "It's not a therapy session."

Image caption Mark Geragos, right, a high-profile lawyer, gets hundreds of media calls

Mr O'Mara heightened tension with his remarks, she says, and made the situation harder for his client. She believes that his remarks hurt his chances for a career as a celebrity lawyer.

"This is O'Mara's 15 minutes of fame," says Ms Levenson. "It's a flash in the pan."