Wednesday will be an important day for a legal principle we hold dear:

Anonymous whistleblowers, with limited exceptions, should feel safe to tip off journalists about governmental matters the public should know.

On Wednesday, a pre-trial hearing is scheduled in Cook County Circuit Court to debate whether Chicago independent journalist Jamie Kalven should be required to disclose the source or sources who alerted him to the now-infamous police dashcam video of the shooting of Laquan McDonald in 2014. Without that tip to Kalven, the public might never have learned about the video, which has sparked a much-needed discussion about police accountability and a push for reform.

Early reports said McDonald had lunged at police just before he was shot, but the video showed he had not.

EDITORIAL

Going after Kalven with a subpoena is a spurious legal tactic. It should have been deep-sixed long ago. We hope Judge Vincent M. Gaughan will use Wednesday’s hearing to quash the subpoena and call it out for what it is: an unnecessary legal sideshow that threatens the public oversight of government.

This should be an easy legal call. Attorneys for Police Officer Jason Van Dyke, who is charged with McDonald’s murder, claim Kalven might have tainted witnesses to the shooting by sharing so-called Garrity documents that relate what police told investigators about the incident. But Kalven clearly has stated he didn’t have access to any such documents, which are confidential.

Even if he did, it’s hard to see how it could affect Van Dyke’s case. In what way would it be relevant to Van Dyke’s defense to know the identity of the source who tipped off Kalven to the existence of the video or other information? Possibly, the defense simply wants to further delay the case. A battle over Kalven, who has said he won’t reveal his sources, could stretch on for months.

The Illinois Supreme Court has ruled that reporters can be required to testify only when their testimony is crucial and all other available sources of information have been exhausted. This case doesn’t meet that test. To do the job of informing the public, reporters need First Amendment protection from lawyers who want to compel reporters to name confidential sources. That’s why Illinois has a so-called shield law to protect journalists.

If the courts allow this issue to drag on, it would set a precedent for any reporter to be subpoenaed on the thinnest of rationales. Would-be anonymous whistleblowers would have even more reason to fear coming forward.

And you, the public, would be left in the dark.

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