Harris Boyle (1953 – 31 July 1975) was an Ulster Defence Regiment (UDR) soldier and a high-ranking member of the Ulster Volunteer Force (UVF), a Northern Irish loyalist paramilitary organisation. Boyle was implicated in the 1974 Dublin and Monaghan bombings, and took part in the attack at Buskhill, County Down when an armed UVF gang wearing British Army uniforms ambushed The Miami Showband at a bogus military checkpoint. The popular Irish cabaret band was driving home to Dublin after a performance in Banbridge. He was one of the two gunmen killed when the bomb they were loading onto the band's minibus exploded prematurely. He is sometimes referred to as Horace Boyle.

Boyle was born in Portadown, County Armagh, and grew up in the working-class Killycomain estate. He was raised as a Protestant and attended Edenderry Primary School. On an unknown date, Boyle joined both the Portadown company of the UDR (as a part-time member) and the Portadown unit of the UVF Mid-Ulster Brigade. He held the rank of major in the latter organisation, which at the time was commanded by Billy Hanna. Despite a vetting process, joint membership of the UDR and loyalist paramilitary organisations was common. Paramilitaries joined to obtain weapons, training and intelligence.

Vetting procedures were carried out jointly by the military Intelligence Corps and the Royal Ulster Constabulary's Special Branch and if no intelligence was found to suggest unsuitability individuals were passed for recruitment and would remain as soldiers until the commanding officer was provided with intelligence enabling him to remove soldiers with paramilitary links or sympathies.

The Hidden Hand: The Forgotten Massacre documentary about the Dublin and Monaghan bombings which was broadcast by Yorkshire Television in 1993 maintained that Boyle was second-in-command to Hanna. The brigade formed part of what later became known as the Glenanne gang. This was a violent loyalist group which operated out of a farm owned by RUC reservist James Mitchell, and comprised rogue elements of Northern Ireland's security forces as well as the UVF and to a lesser extent, the Ulster Defence Association (UDA). This loose alliance carried out sectarian attacks and killings of Catholics, often, although not always, those seen as upwardly mobile, during the 1970s.

Boyle was charged with the possession of weapons and ammunition in suspicious circumstances on 9 September 1972 when he was 19 years old. He was implicated in the Dublin and Monaghan bombings of 17 May 1974. RUC Special Patrol Group officer John Weir named Billy Hanna, Robin Jackson and Davy Payne (UDA) as having planned and led one of the UVF teams that drove three bomb cars into Dublin's city centre during evening rush hour, killing 26 people. His allegations were published in 2003 in the Barron Report which was the findings of the official investigation into the bombings by Irish Supreme Court Justice Barron. According to submissions received by Mr. Justice Barron, the Monaghan bomb (which exploded 90 minutes after the Dublin bombs), was assembled at Boyle's home in Festival Road in the Killycomain estate.

Hidden Hand reported that Boyle (along with Jackson and Hanna) was run as an agent by Captain Robert Nairac, the Military Intelligence Liaison officer attached to 14th Intelligence Company. The programme named Boyle as one of the prime suspects in the Dublin car bombings. Former British soldier and psychological warfare operative Colin Wallace confirmed that Boyle had "close social links" to Captain Nairac. John Weir alleged that Boyle was part of the Glenanne gang who shot a PIRA volunteer (John Francis Green) dead near Castleblaney, County Monaghan on 10 January 1975.

Boyle was one of the Mid-Ulster Brigade UVF gang that carried out the attack against the popular Irish cabaret band, the Miami Showband on 31 July 1975. Author Martin Dillon suggested in his book God and the Gun: the Church and Irish Terrorism that Boyle was one of the leaders of the unit. At about 2.30 a.m., as the band was returning home to Dublin from a performance at the Castle Ballroom in Banbridge, their minibus (driven by trumpeter Brian McCoy) was stopped on the A-1 road at Buskhill, seven miles (11 km) north of Newry, at a bogus military checkpoint by UVF gunmen dressed in British Army uniforms. At least four of the other men, like Boyle, were serving members of the UDR. The band members were lined up with their hands on their heads facing a ditch and asked to give their names and addresses.

Saxophonist Des McAlea, who survived the attack, later testified that Boyle had become angry at some of the other gunmen who had joked with the band members about the success of their performance that night. At this point, Boyle and Wesley Somerville went to the front of the minibus and placed a ten-pound time bomb under the driver's seat. This was meant to explode as the band drove through either Newry or after they reached the Republic of Ireland, killing all five band members on board. According to The Dirty War by Martin Dillon, the plan behind the UVF bombing was to portray the band members as republicans smuggling explosives for the Provisional IRA. As the device tilted on its side, clumsy soldering on the clock which was used as a timer came apart and the bomb detonated prematurely. The bus was blown in half. The two loyalists, both at the centre of the explosion, took the full force of the blast and were killed instantly with their bodies hurled in opposite directions. Boyle's body landed in the road, fifty yards away from the front half of the destroyed vehicle. It was ripped in two and badly burned. Both men were decapitated and dismembered; one limbless torso was completely charred. Survivor Stephen Travers later saw a photograph of one of the dead men and described it: "He didn't have any head, just a black torso, no head, legs or arms." A severed arm with the tattoo "UVF Portadown" was later found a hundred yards from the scene. Boyle was 22 years old at the time of his death. He was unmarried and worked as a telephone wireman.