ANN ARBOR, Mich. -

An Ann Arbor bus agency is vigorously defending itself in a lawsuit related to the rejection of a provocative ad on its vehicles.

Blaine Coleman's ad would have skulls and bones and say, "Boycott Israel. Boycott Apartheid." He believes the Israeli government treats Palestinians unfairly.

Coleman wants the ad on buses that travel near the University of Michigan, but the Ann Arbor Transportation Authority rejected it. In a court filing this week, the agency says it turns down ads that ridicule a group of people. Bus officials say Coleman's ad would make people uncomfortable and have a "negative impact" on ridership.

Federal Judge Mark Goldsmith appears close to making a decision on an injunction sought by Coleman's lawyers. They say his free-speech rights are being violated.