Frustration. Anxiety. Resignation. Those feelings have haunted Brookline Police Department employees in recent months, as the town – and the nation – reckons with issues of social justice and the role of policing in public safety. The result: Brookline police morale is at an all-time low, according to an anonymous survey of Police Department employees. The Select Board’s Committee on Policing Reforms surveyed more than 100 department employees – more than 53% of the department’s total employees – between Feb. 22 and March 6. “The survey found, unsurprisingly, that morale in the department is very low, with 86% calling morale poor and just 3% good or excellent,” according to the committee’s report.