Pirate radio or a pirate radio station is a radio station that broadcasts without a valid license.
In some cases, radio stations are considered legal where the signal is transmitted, but illegal where the signals are received—especially when the signals cross a national boundary. In other cases, a broadcast may be considered "pirate" due to the nature of its content, its transmission format (especially a failure to transmit a station identification according to regulations), or the transmit power (wattage) of the station, even if the transmission is not technically illegal (such as an amateur radio transmission). Pirate radio is sometimes called bootleg radio (a term especially associated with two-way radio), clandestine radio (associated with heavily politically motivated operations) or free radio.
History
Radio "piracy" began with the advent of regulations of the airwaves at the dawn of the age of radio. Initially, radio, or wireless as it was more commonly called at the time, was an open field of hobbyists and early inventors and experimenters. The degree of state control varied by country, for example in the UK, Marconi's work was supported by the post office, but in an era of weak regulation, a music hall magician Nevil Maskelyne deliberately hijacked a demonstration.
The United States Navy began using radio for time signals and weather reports on the eastern coast of the United States in the 1890s. Before the advent of vacuum tube technology, early radio enthusiasts used (electronically) noisy spark-gap transmitters. The navy soon began complaining to a sympathetic press that amateurs were disrupting naval transmissions. The May 25, 1907, edition of Electrical World in an article called "Wireless and Lawless" reported authorities were unable to prevent an amateur from interfering with the operation of a government station at the Washington, D.C. Navy Yard using legal means.
In the run-up to the London Radiotelegraph Convention in 1912, and amid concerns about the safety of marine radio following the sinking of the on April 15 of that year, the New York Herald of April 17, 1912, headlined President William Howard Taft's initiative to regulate the public airwaves in an article titled "President Moves to Stop Mob Rule of Wireless."
United States
In the US the 1912 "Act to Regulate Radio Communication" assigned amateurs and experimenters their own frequency spectrum, and introduced licensing and call-signs. A federal agency, the Federal Radio Commission, was formed in 1927 and succeeded in 1934 by the Federal Communications Commission. These agencies would enforce rules on call-signs, assigned frequencies, licensing and acceptable content for broadcast.
The Radio Act of 1912 gave the president legal permission to shut down radio stations "in time of war". During the first two and a half years of World War I, before US entry, President Wilson tasked the US Navy with monitoring US radio stations, nominally to "ensure neutrality." The US was divided into two civilian radio "districts" with corresponding call-signs, beginning with "K" in the west and "W" in the east, in the regulatory measures; the Navy was assigned call-signs beginning with "N". The Navy used this authority to shut down amateur radio in the western part of the US. When Wilson declared war on Germany on April 6, 1917, he also issued an executive order closing most radio stations not needed by the US government. The Navy took it a step further and declared it was illegal to listen to radio or possess a receiver or transmitter in the US, but there were doubts they had the authority to issue such an order even in war time. The ban on radio was lifted in the US in late 1919.
In 1924, New York City station WHN was accused by the American Telephone and Telegraph Company (AT&T) of being an "outlaw station" for violating trade licenses which permitted only AT&T stations to sell airtime on their transmitters. As a result of the AT&T interpretation a landmark case was heard in court, which even prompted comments from Secretary of Commerce Herbert Hoover when he took a public stand in the station's defense. Although AT&T won its case, the furor created was such that those restrictive provisions of the transmitter license were never enforced.