Once the advocate broke a long silence. ‘Look, Bob, you don’t jump in front of a train just because you don’t like someone’s face in the public gallery.’

‘Granted, Peter. But one of the few visible links between any of the people in this whole series of deaths is the Japanese involvement. Now you’ve brought it up again, I’ve got an itch, and I want to get back to Edinburgh to scratch it.’

Cowan dialled an internal number, and issued instructions to his secretary. Soon afterwards she appeared carrying two folders. Each contained a set of the papers in the Chinese trial.

They read through the notes and transcript in silence. Then Skinner went back to the beginning and listed the facts, point by point.

‘The victim. Shirai Yobatu. She’s twenty, and she’s at Strathclyde University. She’s found strangled in Kelvingrove Park. There are signs of sexual activity which could be rape. Forensic establishes that three men had intercourse with the girl immediately before her death.

‘She was seen earlier from across the street in Park Circus, by another girl student. She was in the company of three oriental men. The girl recognises two of them as waiters in the Kwei Linn Chinese Restaurant off Sauchiehall Street. A lot of the students have eaten there and know the two lads. The witness doesn’t know the other one. No one does. He’s never been found and the. other two wouldn’t name him. It didn’t occur to the witness that Shirai might not have been going willingly with them. She didn’t look under duress.

‘Christ, Peter, the Crown Office made a balls of this, and no mistake. If they’d left out the rape and just gone for a murder conviction they’d have got it no bother. As it was Mortimer and Jameson were able to take the rape charge apart, and to lull the jury into acquitting on both counts.’

Skinner went back to the notes. ‘The accused: John Ho, defended by Mortimer; and Shun Lee, defended by Jameson. They deny the rape charge and it falls apart. They say they didn’t know the third man. They claim that he had just started that day as a dishwasher at the Kwei Linn, and they didn’t know his name. The owner says he only gave the guy a few hours’ work, and he didn’t know it either. He says that the boy was a deaf mute.

‘The lads claim that they had a date for a threesome in the park with Shirai, who, they allege, is a student nymphomaniac likely to graduate with honours - there’s absolutely no evidence of that; her flatmate said she was a quiet girl - and the third guy came along as a spectator. They say that Shirai fancied mystery man too, and that they went off in a huff, leaving her to get on with it.

‘That evening they hear on Radio Clyde that a girl has been found strangled in the park. Mystery man doesn’t show up to wash dishes, and John Ho and Shun Lee decide to do a runner. They separate and go home, but each one is lifted by Strathclyde CID in the act of packing his bags.

‘Mike and Rachel plead panic. The guys are good witnesses; the jury believes them and they walk. So once again, we’ve got two very satis fied clients. Agree?’

Cowan nodded emphatically.

‘But not everybody’s going to be happy with that, are they? What more do we know about Shirai?’ Skinner flicked through the papers before him and found a two-page document, the A4 sheets stapled together. ‘This is the Strathclyde Police report on her background. Let’s see what it says.’

Cowan found the same document in his sheaf of papers; each read quickly.

Skinner summarised aloud as he went along. ‘Interesting. Comes from an above-average family background, even by Japanese standards. And interesting too, she’s not an overseas student, as such.’

The shadow of a smile crept across his face.

‘Her father and mother live in Balerno, of all places. He’s forty-four, managing director of a Japanese pharmaceuticals company in Livingston.’

Cowan looked at him. ‘So he could be a man with a grudge? Not a. dissatisfied client, but the father of a victim. Is that what you think?’

Skinner shrugged his shoulders. ‘It’s the only lead I’ve got, so I’ll have to follow it up. Tell you one thing, I’ll be interested to learn what John Ho and Shun Lee are doing right now. And I can’t wait to show a photograph of Yobatu san to your Advocate Depute pal Harcourt.’

Cowan held up a hand. ‘Hold on Bob; you can link this man to Mike and Rachel through that trial, fair enough. But how can you connect him with the other three murders?’

‘I’ll worry about that later. This is the only bone I’ve got to gnaw on at the moment, and I’m going to give it a bloody good chew.’

Skinner closed his folder. ‘Come with me when I pay a call on Harcourt, once I lay hands on that photo.’