Thursday's landmark decision by the Pakistani high court in Peshawar is a remarkable document: Chief Justice Dost Muhammad Khan examines the US use of drones against Pakistan's tribal areas and reaches several conclusions that, while obvious to most sensible observers, seem to have eluded American authorities for several years.

The case was filed last year by Shahzad Akbar, of the Foundation for Fundamental Rights (FFR), a legal charity based in Islamabad. The case was brought by families of victims killed in a US drone strike on 17 March 2011. The strike – one of more than 300 Obama has launched at Pakistan – is infamous: more than 50 people were killed, including many community elders who had gathered to settle a local dispute over a chromite mine. For the locals it was the equivalent of a strike on the high court itself.

The chief justice's first finding is perhaps the most obvious: "[Drone strikes] are absolutely illegal and a blatant violation of sovereignty of the state of Pakistan." The strikes are, he says, international war crimes, given that there is no state of war between the US and its nominal ally, Pakistan.

It does not matter whether General Pervez Musharraf gave the CIA a wink and a nod when he was the country's dictator. "[T]here is nothing in writing to the effect," writes the chief justice. In any event, no government can legitimately authorise the murder of its own citizens – certainly not without a public announcement through the democratic process. Indeed, Musharraf is currently facing the music for a number of illegal acts he allegedly took while in office.

The American use of drones is, in the chief justice's legal opinion, wholly disproportionate under international law. He notes that 9/11 still provides the US administration's pretext for a "global war on terror", yet there has been "not a single … terror incident … anywhere in the USA" emanating from Pakistan in more than a decade since. How, then, can it be proportionate to kill more than 3,000 Pakistanis, including "infant babies, pre-teen and teenage children, women and others".

Rather than respond with force first and ask questions afterwards, the chief justice orders the Pakistan government to try to solve the dispute through the rule of law. The Pakistan government must make an immediate and genuine complaint to the UN. If the UN security council reaches the appropriate conclusion (which he feels legally it must, absent a US veto), or the general assembly adopts a resolution, and "the US authorities do not comply … the government of Pakistan shall sever all ties with the USA and as a mark of protest shall deny all logistic and other facilities to the USA within Pakistan".

Then he makes another self-evident pronouncement: the Pakistan military's first obligation must be to preserve the security of its own citizens. The "security forces shall ensure that in future such drone strikes are not conducted and carried out within the sovereign territory of Pakistan". Again, rather than shoot first, the government shall administer a "proper warning"; if this does not work, the Pakistan air force must immediately shoot down the drones. Even though I am American myself, I find it hard to argue with this unhappy suggestion: after all, if the Pakistanis were terrorising Texas with Predator drones, I would expect Barack Obama to send the US air force into immediate action.

Ultimately, the US must bear full responsibility for its actions. "The government of Pakistan shall mak[e] a request to the UN secretary general to constitute an independent war crime tribunal, to direct the US authorities to immediately stop the drone strikes ... and to immediately arrange for the complete and full compensation for the victims' families."

This judicial decision is all about democracy and the rule of law. America has held itself out as a proponent of these ideals for more than 200 years. It is a shame that the CIA's supposedly secret drones campaign marks such a sharp departure from both, following on from earlier policy catastrophes such as Guantánamo Bay and Abu Ghraib.

In contrast, Saturday's election marked the first time in its 66-year history that Pakistan has made the transition from one democratically elected government to another. The apparent victor, Nawaz Sharif's PLM-N party, has promised to stop US drone strikes in Pakistan. The court's decision will light a judicial fire under this vow.