There's a kernel of truth to this myth. Many public relations pros got started as journalists at newspapers or at TV and radio stations.
That background helps.
Ex-journalists know the business. They know what reporters and editors need. Also, they have more credibility with the press, and will have relationships with the journalists they knew not only at their old job, but from running into other reporters covering the same stories.
However, it's a myth that you have to be an ex-reporter to do public relations.
There are plenty of people who went straight from college into a PR job. You don't have to major in journalism or public relations, though that certainly helps.
Technically, you don't need a college degree, though most jobs will advertise that they require it.
Working in public relations isn't like being a doctor, lawyer or teacher. Doctors have to do residencies and stand for the boards. Lawyers take the bar exam. Teachers get a license after they already have a college degree in their hot little hands.
In public relations, there's no professional license or test to pass.
The profession is growing, as the demand for information grows. There are more public relations jobs in business, entertainment, politics, non-profits and government. Organizations of all types are seeing the benefit of communicating with the press and public, and they're doing it in more ways than ever: web sites, blogs, Twitter, radio, Facebook, print, e-mail, Youtube videos and television.
It seems like a new way of communicating gets invented or perfected every month. Text messages are replacing e-mail. Facebook ate Myspace. Blogs like Huffington Post are becoming destinations for people looking for news and information.
So you don't have to be an ex-reporter to do public relations. Somebody with technical skills and social media expertise can easily get a job.
However, there are 15,000 ex-journalists who've been laid off from newspapers in the last few years. They're experienced writers. They have mortgages to pay and kids who need braces and resumes that are much better than anybody coming right out of college with any kind of degree.
Many of these people are going into public relations, because those jobs are directly related to what they used to do, and a steady salary with health benefits is a lotbetter than trying to write a blog and hoping banner ads eventually pay the bills.
This won't always be the case. Newspapers can't lay off another 15,000 reporters and editors. Public relations as a profession will continue to grow, and as it does, the jobs will become more specialized.