Robert Lines

Robert Lines (PROSE: The Scales of Injustice, The Lost Boy) often just called Bob, was a policeman. His titles over his career included sergeant (PROSE: The Scales of Injustice) and inspector. (PROSE: Business Unusual, The Lost Boy)

20th century
As a sergeant in Smallmarshes, Bob Lines informed the Third Doctor on the disappearance of Marc Marshall and the emotional state in which they found Barbara Redworth. However, he would not let the Doctor see the cottage where Redworth was found until the following morning. (PROSE: The Scales of Injustice)

Some time after becoming a detective inspector for the Brighton CID, the Sixth Doctor helped him to thwart the Master's attempt to hack into Dow-Jones and Fort Knox. In return, he aided the Doctor's fight against SenéNet. (PROSE: Business Unusual)

Later, he met with Melanie Bush when she returned to Earth after her years of travel with the Doctor. He listened to her describe her experiences, then assured her that her parents missed her and would be "overjoyed" that she was home. He offered to take her home. (PROSE: Missing, Part One: Business as Usual)

Two years after Mel returned, Bob Lines retired from the police. On his retirement day, Trey Korte came, seeking safety from the Magnate. When Trey fell into a self-induced coma, Lines contacted the Doctor. (PROSE: Instruments of Darkness)

21st century
In 2008, Dax Fex Fize Slitheen and Bloorm Vungah Bart Slitheen posed as Jay and Heidi Stafford, and, after they went to the West Ealing Police and reported their son "Ashley Stafford" (actually Luke Smith) as missing, the Chief Inspector took responsibility for the case. He conducted a missing persons report on BBC television together with the disguised Slitheen. Chrissie Jackson recognised Luke on the television and called the police, leading the West Ealing Police and the Chief Inspector to arrive at 13 Bannerman Road, and separated Luke from Sarah Jane, and Luke went to live with who the Inspector believed were the parents of "Ashley". He then took Sarah Jane Smith in questioning at the police station.

After reading files on Sarah Jane from UNIT, he suspected her "powerful friends" of a cover up, but had no real evidence to hold her, so Sarah Jane was allowed to leave, so long as she didn't try to contact "Ashley". (TV: The Lost Boy) Even though Lines investigated Sarah Jane Smith and Luke's life with her, he did not think about investigating the past of the Stafford family. (PROSE: The Lost Boy)

Other realities
A version of Lines, known as Praetor Linus, existed in an alternate timeline where the Roman Empire never fell. He was stationed in Sussex and knew that timeline's Sixth Doctor. (PROSE: Spiral Scratch)