HB 930 (Samuel Rosenberg, D-Baltimore) was introduced Feb. 11, 2004, passing the House 139-1; the companion bill in the senate, SB 464 (Leo Green, D-Prince George's), passed 39-7. The bill was signed by the governor May 11, 2004. Passage of HB 930 came after 10 years of persistent effort to enact an anti-SLAPP law.
An anti-SLAPP bill introduced in the 1996 Regular Session (HB 532) failed. In the 1997 Regular Session HB 134 was introduced; HB 134 was essentially the same as the earlier HB 532. It passed the House 135 - 0 but died in the Senate April 7, 1997. An article on why the bill may have stalled in the Senate, "Ask Sen. Baker Why He Won't Let This Bill Out", was published in the June 4, 1997 County Post (Cecil County).
In 1998 Maryland legislators made a third, unsuccessful, try in as many years to enact an anti-SLAPP statute. Companion anti-SLAPP bills were introduced in the State Senate (SB 399) and House (HB 12).
According to an article in The Daily Record (Baltimore) April 19, 2004, efforts to pass a bill since 1998 were repeatedly stalled by the opposition of Sen. Walter Baker, chair of the Senate Judicial Proceedings Committee, who refused to allow the committee to vote on the bill. In 2002 Baker was not reelected and was replaced as chair of the committee. Nevertheless, when an anti-SLAPP bill did come to a vote in the committee in 2003, it died on a vote of 6-5. Until the successful bill in 2004, anti-SLAPP bills had been consistently opposed by the Maryland Chamber of Commerce, which, however, chose not to testify against the 2004 bill. The 2004 bill was supported by the Maryland State Bar Association.