I can't find Daniel Maclean as yet, but, I did find a Janet Leitch.
Search
www.nas.gov.uk/onlineCatalogue/AD14/38/305 Prerecognition against Janet Leitch for the crime of theft, habit and repute and previous conviction - 1838. Servant, aged 25 years. No fixed abode. Origin, - Glasgow, Moordock Kennedy, Balephuil, Tiree, Argylie.
JC26/1838/399 Trial papers relating to Janet Leitch. 29 September, 1838.
Verdict - Guilty. Sentence - 7 years transportation.
Tried at the High Court, Glasgow. Theft from the smack called the Duncan Malcolm of Tree while it was moored at Broomielaw, Glasgow.
You can send away for the transcripts to the National Archives of Scotland. I had to email them with credit card details for a fifteen pound search fee (non refundable), then when they actually find the papers, they'll give you and estimate. Mine came to sixty-five pounds!! (As mine wasn't a direct line, I didn't go ahead with it, but lost my fifteen pounds).
Hope this all helps, - post again if I wasn't clear enough