A businessman who fought off knife-wielding burglars who were threatening to kill his family was jailed for 30 months in a case that has reignited the debate on how far householders can go to protect themselves and their property.

Munir Hussain, 53, discovered three masked men in his house when his family returned from their local mosque during Ramadan in September last year.

The burglars tied up and threatened to kill Hussain and his family but a teenage son managed to escape and alert Hussain's brother, Tokeer.

The intruders fled when help arrived at the house in High Wycombe, Buckinghamshire, but the brothers chased and caught one, Walid Salem, a criminal with more than 50 previous convictions. He was then subjected to what Judge John Reddihough described as a "dreadful, violent attack" by the Hussain brothers.

Salem was left with a permanent brain injury after he was struck with a cricket bat so hard that it broke into three pieces. The revenge attack was self-defence that went too far, Reading crown court was told.

The judge said Hussain's family had been subject to a "serious and wicked offence" and praised the bravery of his teenage son who escaped.

"This case is a tragedy for you and your families," the judge told Munir Hussain. "Sadly, I have no doubt that my public duty requires me to impose immediate prison sentences of some length upon you. This is in order to reflect the serious consequences of your violent acts and intent and to make it absolutely clear that, whatever the circumstances, persons cannot take the law into their own hands, or carry out revenge attacks upon a person who has offended them."

The brothers, described as family men at the heart of the local community, were found guilty of causing grievous bodily harm with intent after a trial earlier this year.

Munir Hussain was given a 30-month sentence while his brother was jailed for 39 months after the judge decided he had not been subject to as much provocation as his brother.

Although Salem was the only intruder caught after the incident, his injuries meant he was not fit to plead after being charged with false imprisonment. He was given a two-year supervision order at a court hearing in September.

The court heard that the case had similarities to that of farmer Tony Martin, who shot a teenage intruder, and there was public support in both cases. The law allows for people to use reasonable force to protect themselves or others, or to carry out an arrest or to prevent crime.

However, attacks motivated by malice or out of revenge and intended to cause injury are unlikely to constitute reasonable force, according to advice published by the Association of Chief Police Officers and the Crown Prosecution Service.

"It may be that some members of the public, or media commentators, will assert that Salem deserved what happened to him at the hands of you and the two others involved, and that you should not have been prosecuted and need not be punished," the judge added.

"However, if persons were permitted to … inflict their own instant and violent punishment on an apprehended offender rather than letting justice take its course, then the rule of law and our system of criminal justice, which are the hallmarks of a civilised society, would collapse."

The court heard that Hussain and his wife and children feared for their lives as their hands were tied behind their backs.

Michael Wolkind, defending, said Hussain was the "real victim" in the case.

"The public surely do not want Munir Hussain to receive imprisonment. I don't seek a medal, I seek justice for him." Hussain, usually a controlled man, had acted in the heat of the moment in "extreme circumstances of stress", he said.

The prosecution said the Hussains were not being convicted for apprehending Salem, but for the "excessive force" they used on him.

Hilary Neville, prosecuting, said: "What started as reasonable self defence by Munir Hussain then turned into excessive force by virtue of a sustained attack by Munir, Tokeer and at least two others."

The court heard sentencing would have an impact on the local economy, with 10 members of staff losing their jobs at Soundsorba, the company run by Munir Hussain, who employs his brother as a technical director. The firm, which produces sound-absorbing material, has an annual turnover of £2.5m. Munir Hussain is a former winner of the Asian businessman of the year award and is head of the Race Equality Council for High Wycombe.

Speaking outside the court, Wolkind said: "The criminal justice system has failed twice. The court was unable to sentence Walid Salem with sufficient harshness, or Munir and Tokeer Hussain with sufficient compassion.

"It's difficult to believe that this outcome reflects the thinking of the public, or the interests of justice."

He said he intended to appeal against the sentence.

A document jointly published by the CPS and Acpo says people are not expected to make fine judgments about what might be reasonable force in the heat of the moment, so long as they only do what they honestly and instinctively believe is necessary.

However, force used after chasing someone who runs off may not be considered to be reasonable. Acting out of malice and revenge with the intent of inflicting punishment through injury or death would not be reasonable, it adds.

Reasonable force and fatal consequences

Tony Martin

Norfolk farmer who killed a teenage burglar in his home with an illegally held pump-action shotgun in 1999. Martin pleaded self-defence, but was initially convicted of murder and sentenced to life imprisonment. In October 2001 three appeal court judges accepted fresh evidence that he had been suffering from a paranoid personality disorder. The conviction was quashed and his sentence was reduced to five years for the manslaughter of 16-year-old Fred Barras and wounding his accomplice, Brendon Fearon, 30.

Niklos Baungartner

Hungarian businessman who tackled and killed an intruder at his Derbyshire home in 1995. The crown prosecution service ruled out action against him. Baungartner had confronted Robert Ingham, 22, in the kitchen and the fight moved into the front garden, where Ingham suffered a neck injury from which he died. Derbyshire police concluded that Ingham's injuries were entirely consistent with Baungartner's version of events.

Norman Waller

Sentenced to 18 months for affray after killing a gang member he believed to be damaging a neighbour's car in 1992. Waller, 34, of Gateshead, was cleared of murder and two wounding charges, but was found guilty of causing an affray. Terry Malone, 24, died in hospital five days after being stabbed in the chest with a chisel by Waller as the gang surrounded him and his neighbour's son.

Joe Horn

In 2007 Horn alerted emergency services that he could see two men burgling his neighbour's home in Pasadena, Texas. Despite being told by the dispatcher to stay inside, Horn went outside, and subsequently shot and killed both burglars. Last year a grand jury cleared Horn.