Republican Senator Jeff Sessions, the nominee, responded to questions at a Senate confirmation hearing, the first in a series this week for nominees to serve in the Cabinet once Trump enters the White House on Jan. 20.
Protesters charging Sessions has a poor record on human rights interrupted the proceedings several times.
During the 2016 election campaign Trump said waterboarding was an effective interrogation technique and vowed to bring it back and "a hell of a lot worse."
President George W. Bush's administration came under fire when intelligence agencies used the method which simulates the sensation of drowning. More recently Trump has said retired Marine Corps General James Mattis, his nominee for secretary of defense, had persuasively argued against it.
Asked if waterboarding constituted torture, Sessions said Congress has since passed legislation that makes it "absolutely improper and illegal to use waterboarding or any other form of torture."
His stance that the law clearly bans waterboarding could pose a problem for Trump if he tries to reinstate the practice.
Sessions said he would not support banning anyone from the United States on the basis of religion, and said Trump's intentions were to block people coming from countries harboring terrorists, not all Muslims. During his campaign, Trump at one point proposed a temporary ban on Muslims entering the country.
CLINTON EMAILS
Sessions also said he would recuse himself from investigating Hillary Clinton's email practices and charitable foundation if confirmed as attorney general and he would favor the appointment of a special prosecutor for any such investigation.
"I have said a few things," Sessions said about his comments during the presidential race accusing former Democratic presidential candidate Clinton of illegal activity. "I think that is one of the reasons why I should not make a decision in that case." Trump defeated Clinton in the Nov. 8 election.
The gathering was contentious as senators pushed Sessions on his and Trump's positions on issues such as civil rights and immigration.
Sessions was asked how he would handle the issue of former candidate Clinton. Trump said during the campaign that if elected he would ask his attorney general to appoint a special prosecutor to see that Clinton go to prison for her use of a private email server while she was secretary of state and her relationship with her family's charitable foundation.
"We can never have a political dispute turn into a criminal dispute," Sessions said. "This country does not punish its political enemies but this country ensures that no one is above the law."
He said later that he would favor the appointment of a special prosecutor for any investigation into Clinton.
Sessions, 70, became the first sitting senator to endorse Trump for the presidency in early 2016 and has remained an adviser on issues such as immigration. He is being reviewed by the Senate Judiciary Committee, a panel on which he serves, and is widely expected to be confirmed by the Republican-controlled Senate.
Many questions aimed to establish how closely he hewed to some of the positions of Trump.
Sessions said he agreed with Trump in opposing Democratic President Barack Obama's executive action that granted temporary protection to immigrant children brought to the country illegally by their parents and would not oppose overturning it.
Sessions also said he agreed with his many of his fellow Republicans that the military prison for foreign terrorism suspects in Guantanamo Bay, Cuba remain open. The Obama administration has sought to close the prison, opened by former President George W. Bush in 2002, and bring its prisoners to U.S. civilian courts to be tried.
DEFENSE AGAINST RACISM
Sessions several times defended himself against charges of racism. He said allegations that he harbored sympathies toward the Ku Klux Klan, a violent white supremacist organization, are false.
"I abhor the Klan and what it represents and its hateful ideology," Sessions said in his opening remarks.
"End racism Stop Sessions," and "End hate Stop Sessions," read some of the signs carried by protesters.
Sessions was denied confirmation to a federal judgeship in 1986 after allegations emerged that he made racist remarks, including testimony that he called an African-American prosecutor "boy," an allegation Sessions denied.
Democratic Senator Dianne Feinstein said the Senate Judiciary Committee had received letters from 400 civil rights organizations opposing his confirmation to the country's top law enforcement post.
"This job requires service to the people and the law, not the president," Feinstein said.
"There is a deep fear about what a Trump administration will bring in many places. And this is the context in which we must consider Senator Sessions' record and nomination," Feinstein added.
Sessions has opposed abortion and same-sex marriage as a senator, but said on Tuesday that if confirmed as attorney general he would follow the Supreme Court rulings that legalized both abortion and same-sex marriage.
AMERICA'S TOP PROSECUTOR
The attorney general is the country's top prosecutor and legal adviser to the president. As head of the Justice Department, the attorney general also oversees the immigration court system that decides whether immigrants are deported or granted asylum or some other kind of protection.
A key plank of Trump's election campaign was his pledge to deport illegal immigrants and to build a wall along the U.S. border with Mexico.
In 2015, Republicans held up the nomination of Loretta Lynch, the current attorney general, for 166 days, longer than any nominee in 30 years, over her support for Obama's executive actions on immigration.
Sessions, who has represented the deeply conservative Southern state of Alabama for 20 years, has a long, consistent record of opposing legislation that provides a path to citizenship for immigrants. He has also been a close ally of groups seeking to restrict legal immigration by placing limits on visas used by companies to hire foreign workers.
On Monday, a group of civil liberties and internet freedom groups sent a letter to the Senate Judiciary Committee describing Sessions as a “leading proponent of expanding the government’s surveillance authority of ordinary Americans.”
Asked by Republican Senator Orrin Hatch what he would do to protect digital privacy, Sessions said he did "not have firm and fast opinions on the subject."
Sessions said he had not been briefed by the Federal Bureau of Investigation on its conclusion that Russia interfered in the U.S. election campaign to try to tilt the election in Trump's favor, including by hacking into Democratic Party email systems, but he trusted the conclusion was "honorably reached."
For weeks, Trump questioned the U.S. intelligence services' charge that Russia was behind the hacks, although last week he said he accepted this conclusion.
(Reporting by Julia Edwards Ainsley; Additional reporting by David Alexander, Sarah Lynch, Dustin Volz and Ian Simpson; Editing by Frances Kerry and Howard Goller)
