After Prime Minister Narendra Modi’s surprise visit to Lahore, hope was in the air. After eight long years of strained relations, the structure of a composite dialogue was revived. Serious exchanges between the Indian and Pakistani Foreign Secretaries and National Security Advisers seemed possible. And then – no surprise – extremists based in Pakistan carried out an attack to short-circuit improved ties. The target was an Indian Air Force base at Pathankot.

The fingerprints of the Jaish-e-Muhammad appeared to be all over the attack. Phone intercepts were reportedly damning. Pakistan’s civilian and military leaders pledged to get to the bottom of the attack and hold the perpetrators accountable. A coalition of groups based in Azad Kashmir, well-known to Pakistan’s Inter-Services Intelligence, proudly claimed responsibility for the operation. Pakistan’s security forces closed Jaish’s offices and placed its leader, Maulana Masood Azhar, in custody. New Delhi postponed, but did not did not break off plans for high-level meetings, waiting for Pakistan to follow up on its pledges.

As I wrote in this space one month ago, so far, so good. Since then, there are signs that Pakistan’s military and intelligence services are back to business as usual. Pakistani leaders continue to declare strong intent to track down the perpetrators. (Sample: The Interior Minister recently vowed that, “the government will go to any length to win the ongoing war against the menace of terrorism.”) But actions are not reinforcing words. Pakistan’s military and intelligence services have proven their reputation to make progress in tracking down violent extremists. They know how to connect the dots. Yet in the case of the Pathankot attack, trails seem to have gone cold. Put another way, so far there is no strong indication that Pakistan’s definition of violent terrorism extends to those who wish to blow up targets in India.

The Pakistani team investigating the Pathankot attack has reportedly found “no linkage or evidence to suggest that Masood Azhar had ordered the attack or was involved in its planning.” Without such evidence, there will be no trial or no reason to keep Azhar in extended custody. Pakistan’s media reports that low-level cadres of Jaish may, indeed, have been involved, but India would need to supply more evidence and phone intercepts to provide linkages to higher-ups.

This is a familiar story. We heard it after the 2008 Mumbai attacks against luxury hotels, the central train station, and a Jewish center. The perpetrators back then were from another jihadi group, Lashkar-e-Toiba. Evidence of planning from the top was incontrovertible, including phone intercepts and tapes between low-level cadres and their handlers in Pakistan. This evidence was deemed inadmissible in Pakistani courts.

Lashkar-e-Toiba honcho Zaki ur-Rehman Lakhvi was tried but not convicted for the Mumbai attacks because of the absence of prosecution witnesses as well as inadmissible evidence. He was released from custody after six years. Masood Azhar fared better after the 2001 attack on the Indian Parliament. This bold operation, which prompted troop mobilizations in both countries, also seemed to be Jaish’s handiwork. Azhar was detained but not placed on trial, and was released a year later.

Nothing will hurt Pakistan’s attempts to rehabilitate its international standing more than a replay of this script. If Pakistan fails in prosecuting the perpetrators and their handlers, its professions of going to any length to win the ongoing war against the menace of terrorism will be laughed out of the court of international public opinion.

Pakistan’s military and security agencies deserve kudos for continuing to make inroads against violent extremist groups that have turned against the state. After the Pathankot attack, they will deserve brickbats if they fail to extend their campaign against Jaish. India’s leaders deserved criticism for waiting far to long to engage Pakistan. Having finally done so, Pakistan’s leaders are now in the dock. Will they follow up on initial steps against groups like Jaish?

It’s still early. Additional steps can be taken to disprove the thesis of business as usual. If so, relations between India and Pakistan can improve markedly. If not, the onus will be on Pakistan.

This piece originally ran in Arms Control Wonk, February 15, 2016