A university lecturer calls the naval commandos who raided the Mavi Marmara cold-blooded murderers. Another lecturer refuses to permit a student returning from reserve duty to enter the classroom in uniform. A third tells his students that he does not believe reserve duty in the territories justifies absence from class - but he is prepared to excuse the absence of students who attend a protest at a checkpoint.

Yet another lecturer calls for a boycott of Israel because of the occupation. His colleague calls for an academic boycott of Israeli universities, including the one that employs him. Another lecturer's students claim he silences them when they disagree with him.

Or the details could be changed: Perhaps one lecturer calls soldiers who evacuate settlers "Nazis." Another forbids a Muslim student from entering the classroom because she is wearing a veil. A third gives no special consideration to a student called up for reserve duty to evacuate a settlement outpost, but does so for a student who is absent because he went to help thwart an evacuation. And a fourth calls for a boycott on Israel or its universities because the "treasonous" government is prepared to give up parts of the homeland.

What all these scenarios have in common is the pretension that they are protected by academic freedom. But their true common denominator is that they have nothing at all to do with academic freedom. Some of these incidents are protected by freedom of speech, not academic freedom. Others contravene academic freedom.

Let's take criticism of the government: In a democracy, freedom of expression and criticism must be zealously guarded. But what does this have to do with academic freedom?

Indeed, the claim of academic freedom in these matters is somewhat arrogant, as if the faculty were above the people. After all, in a democracy, the voice of a professor is equal to the voice of every other citizen, and rightly so. The pretension of wrapping political critique in academic garb will end up curtailing the right to criticize - as if people who do not enjoy academic freedom should not express their opinions.

Academic freedom goes beyond freedom of expression, and is intended to respond to the needs of the academic community. It is the freedom to study, publish and teach. This is the only way the search for scientific truth can be protected. That is how academics differ from employees of any other institution.

But no one has a monopoly on truth. Thus to protect the search for truth, academics must not suppress the opinions of others, whether students or colleagues - because they too are entitled to academic freedom. Neither may academics force their opinions on others or do harm those whose opinions differ from theirs. The power of academic discourse lies in persuasion, not coercion.

But the greatest threat to academic freedom is the academic boycott. This weapon - even if those who preach it are trying to target government policy - strikes a mortal blow at the freedom to research and develop, because it cuts the scholar off from sources of funding for his research and from colloquy with colleagues, which is essential to academic research.

Nor can we ignore the fact that those who call for a boycott will not be harmed by it themselves. They will enjoy the best of both worlds - both the rights conferred by belonging to the boycotted university and the right to exemption from the very boycott they advocate.

The writer is a professor of constitutional law at Tel Aviv University