Which group would benefit from repealing the high tariffs know as the corn laws? why?

This law benefited the land owners and the nobility who had a large stake in growing corn.  This protected their interest since corn was their main crop.  The ones who suffered were the poor working class whose savings were affected by corn.

Britain held high tariffs in the position that defended the Parliament Agriculturalists. Robert Peel headed the onset to repeal those high tariffs in Britain because they paralyzed global commerce. He compels Parliament members to abolish the Corn Laws to promote free enterprise beyond borders. The Irish Potato Famine really benefited force them to repeal the laws and in the extended period, repealing the Corn Laws covered the distance for free enterprise.

Merchants and tradesmen benefited from the reversal of the tariffs, they could make extra earnings. The Poor and the metropolitan middle groups also benefited because rates overall declined down. Tenants and landowners were degraded.