If you're going to unseat an incumbent, you have to make a crisp case why voters should fire that person.

In Philadelphia's Second City Council District, challenger Damon K. Roberts has not made such a case against Council President Anna Verna.

To be blunt, Verna has not been the most dynamic leader in the history of legislative bodies. For one thing, she has had a hard time preventing loud bullies in the peanut gallery from disrupting Council's business far too often.

Still, she was the president of Council during a period when it surprised skeptics by approving important bills to cut city taxes, reform pay-to-play politics, and protect residents from cigarette smoke.

She enabled those bills to move through Council's murky processes; she was on the right side on most of them, and provided a key vote when Council overrode some misguided vetoes by Mayor Street.

After all that, she should be fired?

Don't think so. The Inquirer endorses ANNA VERNA for another term in Council. Let's add a caveat: It should probably be her last.

Roberts has provided a personable and energetic alternative. But Roberts, an attorney who most recently worked with the Philadelphia Housing Authority (quitting to run for office), simply hasn't framed a persuasive critique of Verna.

He tries to blame her personally for the high murder rate in the district, which includes much of troubled Southwest Philly. That's a stretch. Verna worked hard to find money to hire more police, and helped bring a promising pilot anti-crime program - curfew centers - to her district.

Roberts hasn't lived in Philadelphia long. That's not disqualifying; city natives should move beyond reflexive distrust of anyone not born here. But Roberts' newness shows a bit in his glib way of talking about issues.

Verna, by contrast, is South Philly through and through. Yet, for all her old-fashioned outlook, she ended up being on the right side of most reform issues on Council in her last term.

One good term deserves another.