SALT LAKE CITY » A federal judge on Monday gave a Utah man the maximum sentence of a year in prison for writing a letter threatening to kill white members of an interracial family if they didn’t make a black teenage relative move away.

U.S. Magistrate Judge Evelyn Furse said the threat made by 71-year-old Robert Keller was significant and harmful.

"I hope you will come to regret that even more than you do today," Furse said.

The teenage boy’s sister said Monday she still feels uncomfortable in her neighborhood and worries about her children after receiving the letter last December. The family members’ names have not been released, and the sister declined to be publicly identified Monday.

Prosecutor Carlos Esqueda said Keller was upset because the then-13-year-old boy was walking down the street with a white girl in Hurricane, a southwestern Utah city of about 14,000 people. Esqueda said the case was part of a pattern of racist behavior from Keller, and argued that Keller’s age didn’t excuse his behavior.

"Obliviously, racism still exists today. It lives, and it breathes next door in our neighborhoods," Esqueda said in court. "Justice needs to be firm, and justice needs to be swift."

Keller apologized for sending the expletive-laden letter but said his message was misconstrued.

"I’ll admit I lost my temper," Keller said. "It wasn’t really meant to be a threat; it was more or less to wake them up to what was going to happen down the road."

He did not elaborate.

In September, Keller pleaded guilty to one misdemeanor count of interfering with the right to fair housing in what prosecutors called a hate crime. A second count was dropped, according to court records.

Defense attorney Kent Hart said his client had a tough upbringing but has no history of violence. He said Keller is known for helping his neighbors and volunteering in the community.

"This is not just a one dimensional person here. This is a complicated person who has some old-fashioned sets of ideas," Hart said, though he acknowledged that didn’t excuse the threats.

Following the hearing, Hart called the sentence excessive and disappointing.

The judge also imposed a year of supervised release, a $1,000 fine and 260 hours of community service. There is no parole in the federal justice system.