Barr donated $55,000 to a political action committee that backed Jeb Bush during the 2016 Republican Party presidential primaries and $2,700 to Donald Trump during the general election campaign.
In December 2019, Democratic Senators Ron Wyden and Patrick J. Leahy asked the Justice Department's Office of Professional Responsibility to investigate Barr for approving an illegal surveillance program without legal analysis.
The National Republican Senatorial Committee (NRSC) financially assists Republicans in their Senate election contests; in the seven years from 2009 to 2016, Barr gave six donations to the NRSC totaling $85,400. In a five-month period from October 2018 to February 2019, Barr donated five times (around $10,000 every month) for a total of $51,000. When Barr started donating more frequently to the NRSC, it was uncertain whether then-Attorney General Jeff Sessions would remain in his job. Barr continued donating even after Sessions resigned, and after Trump nominated Barr for Attorney General. The donations stopped after Barr was confirmed by the Senate as Attorney General. NRSC refunded Barr $30,000 before his confirmation. Previously in 2017, Barr had said he felt "prosecutors who make political contributions are identifying fairly strongly with a political party."
In July 2020, Barr condemned large American tech companies, such as Google, Microsoft, Yahoo, and Apple, and Hollywood studios, accusing them of "kowtowing" to the Chinese Communist Party for the sake of profits. He said that "Hollywood now regularly censors its own movies to appease the Chinese Communist Party, the world's most powerful violator of human rights."
Barr supports the death penalty, arguing that it reduces crime. He advocated a Bush-backed bill that would have expanded the types of crime that could be punished by execution. In a 1991 op-ed in The New York Times, Barr argued that death row inmates' ability to challenge their sentences should be limited to avoid cases dragging on for years: "This lack of finality devastates the criminal justice system. It diminishes the deterrent effect of state criminal laws, saps state prosecutorial resources and continually reopens the wounds of victims and survivors."
During his first tenure as AG, media characterized Barr as "a staunch conservative who rarely hesitates to put his hardline views into action". He was described as affable with a dry, self-deprecating wit. The New York Times described the "central theme" of his tenure to be "his contention that violent crime can be reduced only by expanding Federal and state prisons to jail habitual violent offenders". In an effort to prioritize violent crime, Barr reassigned three hundred FBI agents from counterintelligence work to investigations of gang violence. The New York Times called this move "the largest single manpower shift in the bureau's history".
He also advocated the use of Guantanamo Bay to prevent Haitian refugees and HIV infected individuals from claiming asylum in the United States. According to Vox in December 2018, Barr supported an aggressive "law and order" agenda on immigration as Attorney General in the Bush Administration.