Thomson started his career in the Scottish Premier League with Heart of Midlothian, but was loaned to Lithuanian club FBK Kaunas after he was convicted of indecent behaviour involving children.
[2] He made his Scottish Premier League debut three days later at McDiarmid Park in a 2–2 draw with St Johnstone, and was again named as the man of the match by the official Hearts website.
[3] Thomson earned praise from teammate Marius Zaliukas,[4] and won the SPL young player of the month award for September 2009.
[8] Thomson was convicted on 17 June 2011 at Edinburgh Sheriff Court after admitting 'lewd, libidinous and indecent behaviour' towards two girls aged 12 and 14.
[9] Thomson was loaned to Lithuanian club FBK Kaunas, also owned by Hearts majority shareholder Vladimir Romanov, on 31 July.
[28] In June 2011, Thomson was placed on the sex offenders' register for five years and fined £4,000 after he pleaded guilty to two counts of indecent behaviour.
[33] Hearts' decision was criticised by the mother of one of his victims[34] and a children's charity,[35] while a water supplier withdrew their sponsorship of the club.
[37] Hearts announced on 10 July that Thomson would leave the club, following a further disciplinary meeting with majority shareholder Vladimir Romanov.