Anthony Vazquez/Sun-Times City Council members on Friday spent six hours grilling police Supt. David Brown over his plans to tamp down the latest surge in summertime gun violence. But Mayor Lori Lightfoot’s top cop said he could’ve used that time preparing for the perennially bloody Fourth of July Holiday weekend instead. “This briefing before you today comes at a cost of critical scheduled time for our leadership team to discuss deployment decisions that we are all forgoing to ensure you have this information once again,” Brown said before outlining some of the patrol strategies that he and the mayor say are regularly provided to aldermen.