Reality role for a TV D.A.

Just because Fred Thompson has been squiring the new Supreme Court nominee around Capitol Hill doesn’t mean he’s given up greasepaint.

Thompson, a Republican Party stalwart and U.S. senator from 1994 to 2003, is serving as an informal advisor to John G. Roberts Jr., the judge picked last week by President Bush to replace Sandra Day O’Connor on the U.S. Supreme Court.

But while tutoring Roberts on the finer points of Senate relations, the 62-year-old Thompson will have to squirrel away some time to memorize lines. NBC says the attorney-turned-actor is expected to continue his usual duties on “Law & Order,” where he plays craggy, baritone-voiced Dist. Atty. Arthur Branch. The legal drama begins production on its 16th season Friday in New York.

“Fred’s production role will not be affected” by his advisory gig, NBC spokeswoman Cameron Blanchard said. Because of the series’ ensemble nature, Thompson is typically obliged to spend only one production day on the set for each episode (out of eight shooting days total), so the network doesn’t expect problems in working around his schedule.

As a result, TV viewers may witness a surreal blurring of fact and fiction this fall, with newscasts showing Thompson at real-life confirmation hearings, followed in prime time by Thompson’s make-believe D.A. wielding a firm hand over prosecutors and masterminding criminal cases.

As “Law & Order” creator and executive producer Dick Wolf wrote in an e-mail: “With his new presidential assignment, Fred has become the personification of life imitating art imitating life.”

But then Thompson has built a career straddling Hollywood and Washington (a spokesperson said last week that the White House was not making Thompson available for interviews). Since bounding to the national stage as co-chief counsel to the Senate Watergate Committee in 1973-74 (he was credited with feeding Sen. Howard Baker the immortal line, “What did the president know, and when did he know it?”), he’s wrapped his formidable bearing and booming Tennessee accent around a number of meaty character parts in such films as “The Hunt for Red October” and “In the Line of Fire.”

That kind of resume has given Thompson national recognition uncommon among Beltway insiders. During an appearance Monday on “The Tonight Show,” Sen. John McCain of Arizona joked that Thompson himself should be the Supreme Court nominee.

“If I had his voice, I’d be president of the United States,” McCain quipped.

Acting and politics have often overlapped for Thompson. In the late 1970s, he was appointed to investigate allegations that Tennessee Gov. Ray Blanton had illegally sold pardons. Thompson defended the whistle-blower who exposed the corruption, capping his triumph by playing himself in “Marie,” the 1985 movie about the case.

Thompson then acted in several dozen films and television shows before he ran for Senate in 1994 to fill the seat formerly held by Al Gore. He beat out the front-runner in the race by leasing a red pickup truck and driving it around the state to meet with voters, underscoring his down-home image.

He won a decisive reelection in 1996 and then announced in 2002, shortly after the death of a daughter, that he would not seek another term. Before he left office, he joined the cast of “Law & Order” as the new district attorney. Thompson is reportedly paid about $100,000 per episode for his work on the show. (Senators earn about 160,000 per year, although those in leadership positions make more.)

As an actor, Thompson specializes in middle-aged officials who exercise great authority with bedrock decency and subtle humor. Friends say he’s more or less playing himself. Upon arriving at the White House on Tuesday evening to await word of whom Bush had picked, Thompson remarked dryly, “It looks like I’ve got a client.”

Observers say that affable image goes a long way toward explaining why Bush picked Thompson to help guide his nominee through the confirmation process.

Former Republican National Committee Chairman Ed Gillespie is officially supervising the White House efforts to get Roberts confirmed. Gillespie, now a political consultant, doesn’t shy from partisan infighting, but Thompson provides a less ideological public face.

“The subtext is that if Fred Thompson is taking the nominee around, he’s probably somebody who isn’t too extreme,” said Stuart Rothenberg, an independent political analyst.

Charles Cook, a Washington-based analyst who publishes the Cook Political Report, agreed. “He comes across as very plain-spoken, reasonable and has an enormous amount of credibility,” Cook said. “I think it was kind of an inspired move on the part of the White House -- and I don’t think NBC minded a bit.”

Thompson has been advising Roberts about the customs and practices of the Senate, as well as the Judiciary Committee process. He is escorting him around the Capitol, where the nominee is meeting with about five or six senators a day. (However, at least one senator -- Democrat Edward M. Kennedy of Massachusetts -- asked Roberts to come without his handler.)

Aides who have sat in on meetings Thompson attended said that he has largely stayed to the sidelines while Roberts chats with the lawmakers, jumping in only when a question arose about the White House position on a subject.

The Bush administration has also tapped the ex-senator to be one of its public faces in the confirmation process. On Sunday, he discussed Roberts’ selection on NBC’s “Meet the Press.”

His approachable style somewhat masks Thompson’s political leanings, which are more conservative than his bipartisan friendships might suggest.

His voting record in the Senate was staunchly conservative, earning a 92% rating from the American Conservative Union. And he has frequently lent his performance talents to causes dear to the Bush White House.

Thompson did the voice-over for the video introducing the president during last summer’s Republican National Convention. He also has close ties to Citizens United, a Washington-based advocacy group that was a scourge of the Clinton administration and has funded ads backing Bush’s agenda.

In one 30-second commercial that was funded by Citizens United and aired nationwide just before the Iraq invasion in 2003, Thompson told viewers: “With all the criticism of our president’s policy on Iraq lately, Americans might ask, ‘What should we do with the inevitable prospect of nuclear weapons in the hands of a murderous and aggressive enemy? Can we afford to appease Saddam?’ ”

Citizens United President David Bossie described Thompson, a longtime friend, as “a Ronald Reagan Republican ... a populist Reagan conservative.”

Still, over time Thompson has gained a reputation as a moderate, partly because of his support for government reform, including campaign finance legislation, and partly no doubt due to his instant recognition with movie and TV audiences.

Bossie said he’d like to see Thompson run for president in 2008, but quickly added: “I know he’d not like to hear that.”

Other friends agree that another shot at high office is probably not in the cards for Thompson. Barbara Comstock, a Washington attorney and former Justice Department spokeswoman who is friends with Thompson and his wife, said the ex-senator is “pleased to be part of this process and help get a great nominee on the court.”

But as much as Thompson enjoys temporarily being back on the Hill, Comstock said, he also relishes his post-Senate life -- not only his “Law & Order” role, but also being the father of a 20-month-old daughter.

“He always talks about how people shouldn’t be in government forever,” Comstock said. “He’s really enjoying his life now.”