`Do I know the snatch?'

`A weasel called Castus.'

It meant nothing. I didn't ask if I knew the prostitute, and Petro didn't bother to embarrass anyone by naming her. `So what about your star witness? What about Nonnius?'

`We were well set up by the time our barrister called him. All Nonnius Albius had to do was to confess his own role as a Balbinus collector, and state that he knew the killer Castus was on the Balbinus payroll. He played his part very prettily – he even produced tallies to show the percentage Balbinus regularly took from stolen purses at the brothel.'

`Good value!'

`A prime witness. Our Lycian had come up with some joyful clinchers, like Castus exclaiming as he stabbed the dead man, "Teach him to argue with Balbinus!" Nonnius then told the jury that all the Balbinus henchmen are routinely ordered to slash if trouble threatens. He had frequently heard Balbinus give those instructions. So we had him for organised crime, profiteering, and conspiracy, resulting in actual death.'

`The jury bought it?'

`Marponius had explained to them that he needed their cooperation if he was to be seen as the judge who cleaned up Rome.

Marponius was the main judge in the murder court. He was keen on his work, and personally ambitious, though not necessarily as blatant as Petronius made out. For one thing, Marponius was not a clever man.

`There were some juicy details,' Petro said. `I was threatening Lalage with a range of offences against the prostitutes' registration rules, so even she went into court to give evidence on our side.'

`Couldn't Balbinus buy her off?'

`I reckon she's keen to see him take a trip,' opined Petronius. `Lalage would be quite capable of running Plato's on her own. Maybe things were different once, but nowadays she really doesn't need a king of crime creaming off the top of her income.' He leant back and went on with his usual modesty: `Oh I had some luck in the timing. Balbinus believed himself untouchable, but there was a new mood in the underworld. People were ready to revolt. I noticed the change before he did, that's all.'