Democratic politicians all over the state are being forced to re-examine their options in the wake of the rejection of House Speaker John Hanson Briscoe for a seat on the Court of Special Appeals.

The elevation of Briscoe to the state's second highest court was such a foregone conclusion that at least three members of the House of Delegates were lining up support to succeed him as speaker. Now that Briscoe is going to be back for another season, their ambitions have been delayed, or maybe even sidetracked.

The contenders were John S. Arnick, Benjamin Cardin and Joseph E. Owens. All three are committee chairmen with impressive credentials.

The ramifications of Briscoe's rejection may be felt beyond the legislative chamber. Without the imminent prospect of a life-long job as a judge, Briscoe might turn his attention to statewide political office, thereby interferring with plans of other candidates for such high jobs as attorney general or lieutenant general.

Fortunately, for the sake of party unity, neither Arnick, Cardin nor Owens had done much more than encourage support for their hopes to become speaker.

"In politics, you never have a schedule," said Cardin, chairman of the Ways and Means Committee. "If you do, you never keep it." He acknowledges telling "two or three dozen" members of the House that he would like to be speaker if a vacancy occurred. "There was lots of talking but no doing," Cardin said. "I didn't want to make a move until John Briscoe's name was on the list" for a judgeship.

Arnick, who is both majority leader and chairman of Environmental Matters Committee, said he was "not overtly campaigning." Like Cardin, he was going to make an all-out race if Briscoe was named to the court.

Owens, the judiciary committee chairman from Wheaton whose latest accolade from the committee staff is a T-shirt that says "crafty, crusty and cantankerous," also said that "activity would have accelerated this week" if Briscoe had been picked.

Cardin, Arnick and Owens agree that Briscoe is qualified for the court, but they offer various guesses as to why he wasn't tapped.

Arnick thinks the judicial selection committee may have resented the widespread reports that Briscoe had the spot wrapped up, and bypassed him to show its independence.

"It might also be part of a general anti-politics feeling" that exists as the result of the conviction of Gov. Marvin Mandel on political corruption charges, he said.

Briscoe, searching for a reason, recalled that he testified as a witness in behalf of Mandel at the trial, "something that I'm not a bit ashamed of."

Owens said he hopes that a post-Mandel morality "wouldn't reflect adversely on John. He would make a good judge. They made a mistake."

One winner in the decision may be Acting Gov. Blair Lee, who should have an easier time getting his programs through the legislature - and therefore a record on which to run - with the steady, respected Briscoe presiding over the lower chamber.

Politics as Art-Paintings illustrating the Mandel trial are on exhibit at the Foundry Gallery at 2121 P St. NW. near DuPont Circle in Washington. Artist Ann Munro Wood, who covered the trial for Channel 9 (WTOP) has about 60 illustrations on display. Included are closeups of Mandel and his co-defendents, the judge, prosecutors and defense attorneys, and many of the witnesses, including a number of legislators.

Wood turned out three to 10 sketches a day, which were transmitted by microwave from Baltimore to the Washington television studio each day in time for the evening news. The paintings, 15 by 20 to 18 by 24 inches, sell for $85 to $250.

In addition to the Mandel trial, paintings of the Hanafi trial, done by Mrs. Wood's sister, Roxie Munro, are part of the exhibit.

Gilchrist for County Executive - those words, emblazened on 5,000 red, white and blue bumper stickers, mark the first public announcement by a candidate for the top job in Montgomery County.

State Sen. Charles W. Gilchrist, a 40-year-old Rockville tax lawyer, picked up $10,500 at a Friends of Charley Gilchrist fund-raiser in June. He said he will make a formal announcement and pay a filing fee later this year or early in 1978.

Other Democrats mentioned as possible challengers are Royce Hanson, Sid Kramer, John Menke and Joe Anastasi. The big challenge, of course, is likely to come from the incumbent Republican James Gleason, who may try for a hat-trick third-term in heavily Democratic Montgomery.