Ramallah - A recent plea deal for an Israeli police officer who killed a Palestinian teenager has highlighted a broader policy of leniency in Israel for offences committed against Palestinians, analysts say.

"The police, the army, the investigative units, the public attorney and the judiciary are all in concert protecting each other ... They see Arabs, whether an Arab citizen [of Israel] or Arab [in Palestine], as the enemy," lawyer and human rights activist Yamen Zeidan told Al Jazeera. "We do not bet on the integrity of the judicial system, but that doesn't mean that we will stand with our arms crossed."

Israeli police officer Ben Deri - who shot and killed 17-year-old Palestinian teenager Nadim Nuwara in May 2014 - was freed from house arrest in January after a surprise plea deal between the office of the Israeli public prosecutor and Deri's lawyer. Under the plea deal, Deri will only face negligent murder and aggravated assault charges, instead of the initial charge of second-degree murder.

The victim's family is now contesting the deal at Israel's High Court, as it was reached without their knowledge, violating the state's victim protection act. The court will hear arguments on May 29.

"It is my duty towards my son to do all I can [to bring justice] and to have no regrets that I didn't do enough," Siam Nuwara, Nadim's father, told Al Jazeera. "I want to expose Israel's charade courts and I want to exhaust all local court proceedings before going to international courts."

READ MORE: Israeli army 'among world's child rights violators'

The Nuwara family's lawyer, Feras Assali, said the charges against Deri were lowered amid intense public and political pressure spurred in part by the trial of Elor Azaria, the Israeli soldier who shot and killed an incapacitated Palestinian in the city of Hebron last year. Some Israelis have called for Azaria to be pardoned.

Nuwara expressed interest in eventually bringing his own son's case before a global forum, such as the International Criminal Court.

"I began making contacts with international lawyers from abroad, and we are gathering data and evidence to present to the United Nations because these are our kids - we are doing this for our kids," he said. "We are taking this step to prevent Israeli soldiers from killing our children."

Deri was honourably discharged from the Israeli police force in October 2014, without any disciplinary action taken against him.

Assali said that he does not believe the High Court will ultimately quash the plea deal, but the family members are nonetheless determined to present their arguments.

"We will raise the victim protection act, which prohibits the discussion of a deal without the consent of the victim's family," he told Al Jazeera, noting that he will argue the public prosecutor signed the plea deal "under political pressure and a charged public atmosphere".

The Israeli chief prosecutor of the Jerusalem district did not respond to Al Jazeera's request for comment. According to Assali, the public prosecutor's office justified the deal by stating that there was not enough data to support that Deri had fired his weapon with intent to inflict a fatal wound.

We are taking this step to prevent Israeli soldiers from killing our children. Siam Nuwara, father of Nadim Nuwara, killed in 2014

An autopsy revealed that Nadim died from a single bullet wound to the chest. Defence lawyer Tzion Amir said that his client mistakenly fired a live round when he was thought he was firing a rubber-coated steel bullet.

However, Assali has rejected this argument, noting that it was not technically possible, as rubber-coated bullets would require a special gun attachment. He also cited evidence that at least three Palestinians were hit with real bullets during the same Nakba Day protest in the village of Beitunia. Nadim did not pose a threat at the time, Assali said.

The plea deal for Deri highlights a wide-ranging policy of leniency in the Israeli justice system with regards to offences committed by Israelis against Palestinians, experts note.

Human rights group B'TSelem notes that Israel, with the exception of the Azaria case, has not investigated any cases since September 2015 in which Palestinians were killed in relation to stabbings or alleged stabbings. More than 300 Palestinians have been killed since a fresh wave of violence erupted in late 2015.

Data published by B'TSelem on Palestinian civilian fatalities as a result of Israeli army operations between April 2011 and December 2015, meanwhile, showed that of 121 Palestinian fatalities, there was only one indictment and one conviction.

READ MORE: Report slams Israel's military law enforcement system

Israel has also been criticised for showing leniency in cases of settler violence; one infamous example is the case of Muhammad Abu Khdeir, the Palestinian teenager who was kidnapped and burned alive in July of 2014. The Israeli perpetrators were eventually put on trial and convicted of murder, but when the victim's family demanded that Israel demolish the homes of his killers - a policy that is standard practice for Palestinian attackers - the state rejected the motion, claiming it was an isolated incident rather than "collective" violence.

Hussein Abu Khdeir, the victim's father, told Al Jazeera that in his motion to the court, he cited dozens of attacks committed by Israelis against Palestinians, pointing to a culture of incitement in Israeli society against Palestinians. The burning of the Dawabsheh family home in the summer of 2015 was another grim example.

The scope of human rights abuses committed by Israelis against Palestinians is alarming, human rights groups say.

Nisreen Alyan, an advocate with the Association for Civil Rights in Israel, noted that it was very difficult to obtain indictments against Israeli officers because of the challenges in obtaining evidence from the police or the army. "The situation is very difficult; the victim has to gather evidence and to do the follow-up," Alyan told Al Jazeera.

The Israeli NGO Yesh Din says that as many as one-third of Palestinian victims opt not to file complaints because they do not trust the Israeli police to carry out a thorough investigation.

And last year, B'TSelem announced that it would no longer cooperate with Israel's military law enforcement system "because after 28 years of filing complaints, nothing has changed", B'TSelem researcher Karim Jubran told Al Jazeera.