The US judge derided by Donald Trump on Twitter after blocking the president's executive order on immigration is known for his conservative legal views.
udge James Robart has a record of helping disadvantaged children that includes fostering six of them, and for dramatically declaring "black lives matter" during a hearing on police reform in 2015.
The 69-year-old was appointed to the bench by President George W Bush in 2004, following a distinguished 30-year career in private practice, and has donated to the Republican Party.
He made the most high-profile ruling of his tenure on Friday when he temporarily invalidated Mr Trump's ban on travel to the US from seven primarily Muslim nations.
The ruling did not sit well with the president, who on Twitter called him a "so-called judge" and the ruling "ridiculous".
The president later falsely claimed the decision meant "anyone, even with bad intentions, can come into US".
The comments are unlikely to sway Judge Robart, said those who know him.
"Jim will give a wry smile, maybe adjust his bowtie a little bit and go back to doing his business," said former Seattle US attorney John McKay, who worked with Judge Robart for a decade at the law firm of Lane Powell Spears Lubersky.
"He's a very careful judge, and he's conservative in the sense he looks at the law and tries to determine what that is, not what he wants.
"He's conservative in his review of the law, but courageous in his application of it."
Another former Seattle US attorney, Jenny Durkan, called Judge Robart exacting.
She said: "We won some in front of him and we lost some in front of him, but we knew any time we walked into his courtroom we'd better be prepared."
That was evident on Friday when the judge grilled Justice Department lawyer Michelle Bennett.
He asked if foreign nationals from the seven countries named in the order had been arrested for plots in the US since 9/11, and she said she did not know.
"The answer to that is none, best I can tell," Judge Robart said.
"You're here arguing on behalf of someone that says we have to protect the United States from these individuals coming from these countries, and there's no support for that."
The judge, a graduate of Georgetown Law School, is an expert in patent and intellectual property law.
He is considered a tough sentencing judge in criminal matters, especially in cases involving white-collar defendants.
And he has overseen reforms at the Seattle Police Department since 2012, when it agreed to make changes in response to Justice Department findings that its officers were too quick to use force, especially in low-level situations.
Judge Robart was holding a hearing in that case in summer 2015 - a time fraught with tension over violence by and against police officers around the country - when he surprised the courtroom by adopting the mantra of protesters.
"The importance of this issue to me is best demonstrated by the news," he said.
"According to FBI statistics, police shootings resulting in death involve 41% black people, despite being only 20pc of the population living in those cities, 41pc of the casualties, 20pc of the population: Black lives matter."
He donated to the state Republican party and candidates before becoming a judge, but was picked for the bench with the help of a bipartisan selection panel.