SALEM — Lawrence Mayor Brian A. DePeña pleaded not guilty Tuesday in Essex Superior Court to charges stemming from allegations that he secretly recorded two municipal employees at City Hall and distributed the recordings. DePeña, 61, faces 14 counts of distributing a wiretapped communication and one count of witness intimidation, according to court filings. The charges are allegations; DePeña’s not-guilty plea means the case remains unresolved. He was released on personal recognizance. His next hearing is scheduled for Dec. 9. The case puts the conduct of Lawrence’s chief elected official under scrutiny as it moves through the state court system. The available court information does not detail the alleged intimidation or identify the employees involved.