A court has sentenced four relatives over the 2011 kidnapping and assault of a gay man in the US state of Kentucky.

David Jenkins, 39, will spend 30 years behind bars, his younger cousin, Anthony Jenkins, was jailed for 17 years yesterday.

Last October, the pair were found guilty on charges of kidnapping and conspiracy to kidnap, but they were both acquitted of federal hate crime charges in a major blow to the US Justice Department.

Two female relatives who pleaded guilty to the conspiracy to kidnap and assault the victim – as well as taking part in a hate crime – were also sentenced on Wednesday.

The women were the first to be convicted under the federal sexual orientation provision to the hate crime law.

Mable Jenkins, 20, received eight years and four months, and Alexis Jenkins, 20, was sentenced to eight years.

During the trial the two women testified against their male relatives.

The wife of Anthony Jenkins spoke of how the two men bragged about attacking the victim and used homophobic language.

It was alleged they yelled obscenities and anti-gay slurs at Kevin Pennington while trying to beat him to death in Kingdom Come State Park in Harlan County, on 4 April 2011

However, during the trial, lawyers for the accused said it was for reasons other than Mr Pennington’s sexuality and cited how Mr Pennington was looking to purchase drugs from the two men.

The 18-year-old brother of Anthony Jenkins told jurors that the two men laughed about assaulting the victim and said they did it because the man is gay.

But the jury found the men not guilty of committing a hate crime.

The case was the first in the US to involve a charge linked to the violation of the Matthew Shepard-James Byrd Jr. Hate Crimes Prevention Act, which was passed in 2009.

The law was named after Matthew Shepard and James Byrd Jr. Both men were attacked and killed in separate incidents in 1998 that drew US attention to the need to toughen hate crime laws.

Shepard was gay, and Byrd was killed in a racially-motivated attack.