Tony Blair’s government set up devolved institutions and abolished most hereditary peers, without attempting to link these reforms. Scottish peers have mostly belonged to the three main British parties. Devoid of any electoral mandate, they have taken a keen interest in debates related to devolution, or with a major impact on it (Brexit). This article contends that while peers from Scotland backed extensions of devolution over its first twenty-five years, they were wary of any move likely to be interpreted as supporting the Scottish National Party (SNP) and its independence plan. In turn, SNP politicians, who have refused to sit in the upper House, occasionally found allies in the House of Lords to defend Scotland’s autonomy.