Lana Jean Rawls, the woman who is Hamilton Jordan's accuser in the most recent cocaine-sniffing incident in Los Angeles is represented by one of the most publicity-savvy law partnerships in Beverly Hills.

Irving A. Osser, Rawls' lawyer, says his client is prepared to tell the Justice Department she was with Jordan in 1977 when he allegedly used cocaine at a dinner party. Osser is the lesser-known partner in his firm. He is the brother-in-law of Paul Fegen, also his partner, and a man who knows how to put on a performance guaranteed to get media coverage.

In 1975, he rented the biggest ballroom at the Century-Plaza Hotel and invited 1,400 people, along with reporters and photographers, to come and see him get his hair cut and his long beard shorn by the hair stylist who was reportedly the model for Warren Beatty's swinging hairdresser in the movie "Shampoo."

Recording artists Tower of Power were hired from Warner Bros. to provide the background music and comedian Marty Allen to act as announcer.

Fegen was already known to the local press as "something of a character," according to a story in the Los Angeles Times the next day.

He was known for riding around in his expensive and exotic Excalibut, a black German shepherd at his side, with special loudspeakers hooked up to allow him to hail pretty girls as he passed. He boasted of a card file of 2,000 phone numbers and was the host of a regular Friday night party that was an open house "to anybody who knew about it."

Just recently, Fegen gave a birthday party for his current girlfriend at "Flipper's," a roller disco, that brought out the television cameras in droves.

Together, Fegen and Osser owned a swinging bistro known as "Horticultural Holiday." Fegen says he himself "hung out" at Sergio's, the club where Mrs. Rawls picked up Ham Jordan's entourage on the night in question.

Fegen was Mrs. Rawls' lawyer originally, representing her seven or eight years ago in a "noncriminal" matter he won't discuss. When she divorced blues singer Lou Rawls, Fegen says, he turned her divorce over to his partner because Fegen has been devoting himself more and more to a real estate venture that leases office space to other lawyers.

Osser's name surfaced last weekend in connection with the Jordan affair when reporters trying to locate Mrs. Rawls traced him through her divorce records.

Osser has been promising all week to produce Mrs. Rawls for a press conference in Los Angeles that should get more coverage than the roller-skating party.

But reporters who have been so eager to talk with her in person may find they should start looking closer to home for sources on what actually happened in Los Angeles the night of Oct. 21, 1977.

Mitchell Rogovin, the Washington lawyer whose tip sent the FBI and the press in pursuit of Mrs. Rawls in the first place, says he first heard allegations that drugs were used on that White House trip to California from someone in Washington he has known for a number of years.

He hints that his source may have been a journalist who found himself or herself in "a conflicting role."